Power Equipment and Engineering Standards
CenturyLink ™
Technical Publication
Power Equipment and Engineering
Standards
Copyright 1996 - 2015
Printed in U.S.A.
All Rights Reserved
77385
Issue K
July 2015
PUB 77385
Issue K, July 2015
Notice
NOTICE
All requirements in this document are effective from the publication date of the document forward.
This document should be used in conjunction with CenturyLink ™ Technical
Publications 77350, 77351, 77355, and 77354; Telcordia ® Recommendations; Alliance for
Telecommunications Industry (ATIS) documents; American National Standards
Institute (ANSI) documents; Institute of Electrical and Electronics Engineering (IEEE) standards; Federal Communications Commission (FCC) rules; the National Electrical
Code (NFPA ® 70); Underwriters Laboratories Requirements; Department of Labor -
Occupational Safety and Health Standards (OSHA 29 CFR, Part 1910); and Federal,
State, and local requirements including, but not limited to, statutes, rules, regulations, and orders of ordinances imposed by law. Detail engineering for CenturyLink ™ sites shall meet all of the above references, as well as CenturyLink ™ Standard Configuration
Documents.
The origin of this Technical Publication 77385 was in 1996. Prior to that point, power requirements for USWEST were contained in Module C of Technical Publication 77351.
CenturyLink ™ reserves the right to revise this document for any reason, including but not limited to, conformity with standards promulgated by various governmental or regulatory agencies; utilization of advances in the state of the technical arts; or to reflect changes in the design of equipment, techniques, or procedures described or referred to herein.
Liability to anyone arising out of use or reliance upon any information set forth herein is expressly disclaimed, and no representation or warranties, expressed or implied, are made with respect to the accuracy or utility of any information set forth herein.
This document is not to be construed as a suggestion to any manufacturer to modify or change any of its products, nor does this publication represent any commitment by
CenturyLink ™ to purchase any specific products. Further, conformance to this publication does not constitute a guarantee of a given supplier's equipment and/or its associated documentation.
Ordering information for CenturyLink ™ Technical Publications can be obtained from the Reference Section of this document.
PUB 77385
Issue K, July 2015
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PUB 77385
Issue K, July 2015
Table Of Contents
CONTENTS
Chapter and Section Page
General Requirements and Definitions .................................................................. 1-1
General ............................................................................................................. 1-1
Reason For Reissue ........................................................................................ 1-2
Requirement Applicability ........................................................................... 1-2
AC Requirements ........................................................................................... 1-3
AC Surge Suppression ................................................................ 1-7
Generic Technical Requirements ................................................................. 1-7
NEBS ™ Requirements .................................................................................. 1-10
Generic Alarming Requirements ............................................................... 1-12
DC Power Plants and Rectifiers ............................................................................... 2-1
Overview ......................................................................................................... 2-1
General DC Power Plant Requirements ..................................................... 2-1
Charging Equipment (Rectifiers) and Their Controller ........................... 2-6
Engineering Guidelines ................................................................................. 2-9
Example of Proper Calculation and Usage of List 1 and
List 2 Drains ................................................................................ 2-12
Power Board Panel and Fuse Numbering for New Plants .................... 2-16
Conventional Controller ............................................................................. 2-17
Batteries ....................................................................................................................... 3-1
Overview ......................................................................................................... 3-1
General Description ....................................................................................... 3-1
Battery Discharge Characteristics ................................................................ 3-1
Battery Recharge Characteristics ................................................................. 3-3
Ventilation of Battery Areas ....................................................... 3-4
Battery Configurations .................................................................................. 3-5
Battery Types .................................................................................................. 3-6
Selection ......................................................................................................... 3-10
Sizing .............................................................................................................. 3-11
Battery Stands and Connections ................................................................ 3-12
Metal Stands, Trays, and Compartments/Boxes .................. 3-12
Round Cell Stands...................................................................... 3-13
Battery and Stand Installation and Intercell Connections.... 3-14
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Table Of Contents PUB 77385
Issue K, July 2015
CONTENTS (Continued)
Chapter and Section Page
Converters ................................................................................................................... 4-1
General ............................................................................................................. 4-1
Alarm Features ............................................................................................... 4-1
Technical Requirements ................................................................................ 4-1
Line Powering................................................................................................. 4-3
Introduction to Line-Powering .................................................. 4-3
Nominal Line-Powering Voltages ............................................. 4-3
Pairs and Wire Gauges Used in Line-Powering ...................... 4-4
Line-Powering Current and Power Limits ............................... 4-6
Transmission Power Loss ........................................................... 4-7
Human Susceptibility Thresholds for Voltage and Current .. 4-8
Safety Precautions for Line-Powering Voltages Above 60 .... 4-9
Current-Limiting of Higher Voltage Ground Faults ............ 4-10
Additional Concerns Above 300 VDC Across the Pairs ....... 4-11
Inverters (DC/AC) ..................................................................................................... 5-1
General ............................................................................................................. 5-1
Inverter Selection ........................................................................................... 5-2
Load Classification ......................................................................................... 5-2
Alarm Features ............................................................................................... 5-2
Technical Requirements DC and AC Power Supplies .............................. 5-3
Uninterruptible Power Supplies (UPS) .................................................................... 6-1
Standby Engine-Alternators ...................................................................................... 7-1
General .............................................................................................................. 7-1
Site AC Power Systems .................................................................................. 7-3
Sizing and Ratings .......................................................................................... 7-4
Alternator Technical Requirements ............................................................. 7-5
Control Cabinet and Transfer System Requirements ................................ 7-6
Additional Engine Requirements ............................................................... 7-11
Voltage and Frequency Regulation ............................................................ 7-12
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Table Of Contents
CONTENTS (Continued)
Chapter and Section Page
Additional Paralleling Requirements ........................................................ 7-14
Alarms and Shutdowns ................................................................................ 7-15
Power System Monitor/Controller (PSMC) and Battery Monitors ..................... 8-1
Standard Monitor and Control Points ......................................................... 8-2
Primary Power Plant ................................................................... 8-2
Rectifiers ........................................................................................ 8-3
Batteries ......................................................................................... 8-4
Converter Plants ........................................................................... 8-5
Inverters ......................................................................................... 8-5
Residual Ringing Plants .............................................................. 8-6
Uninterruptible Power Supplies (UPS) ..................................... 8-6
Standby Engines and Transfer Systems .................................... 8-6
AC Power ...................................................................................... 8-8
Energy Management and Sequencing ......................................................... 8-9
Requirements of a PSMC for Small Sites, or Battery Monitor for UPS ... 8-9
Primary Power Plant ................................................................. 8-10
Rectifiers ...................................................................................... 8-10
Batteries ....................................................................................... 8-11
Power Alarms in Sites Without a PSMC ................................................... 8-12
DC Power Distribution ............................................................................................... 9-1
General .............................................................................................................. 9-1
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CONTENTS (Continued)
Chapter and Section Page
Telecommunications Equipment Loads ...................................................... 9-1
Power Plant Distribution Characteristics .................................................. 9-13
Cabling and Bus Bar ..................................................................................... 9-14
Protectors and Cable Sizing ......................................................................... 9-19
DC System Fuse and Breaker Sources ....................................................... 9-21
Bus Bar Labeling and Layouts .................................................................... 9-32
Ring, Tone and Cadence Plants .............................................................................. 10-1
Ringing and Tone Systems Technical Requirements ............................... 10-1
Ringing Plant Alarms and Troubles ........................................................... 10-3
Power Pedestals ........................................................................................................ 11-1
Lighting ..................................................................................................................... 12-1
Standard Alarm Messages and Threshold Settings for Power .......................... 13-1
Power Alarm Standard Messages Reporting to NMA
® ......................... 13-2
3 TL1 Query Messages for Power ............................................................... 13-30
Set Points (Thresholds) for Power Alarms and Power Routines ........ 13-32
Typical Power Alarm and Monitor Points ............................................. 13-42
13.6 Power SNMP Traps ................................................................................... 13-44
Detail Power Enginering Checklist ....................................................................... 14-1
Detailed DC Power Engineering Audit .................................................... 14-1
Power Plants ............................................................................... 14-1
Batteries ....................................................................................... 14-3
What Cable Racking is Required? ........................................... 14-4
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Table Of Contents
CONTENTS (Continued)
Chapter and Section Page
How Much Cable is Piled on the Rack and is it Blocked? .... 14-4
Floor Loading of Equipment .................................................... 14-4
Converter Plants ......................................................................... 14-4
Ringing Plants............................................................................. 14-4
AC Equipment ............................................................................ 14-5
Standby Engine Alternator ....................................................... 14-5
Battery Distribution Fuse Boards (BDFBs) ............................. 14-6
Turn Up, Test, and Acceptance Procedures ......................................................... 15-1
Maintenance Window Guidelines for Power .......................................... 15-1
Definitions and Acronyms ...................................................................................... 16-1
Bibliography ............................................................................................................. 17-1
® and Bell Labs Publications ...................................................... 17-1
™ Technical Publications ...................................................... 17-3
Tables
Operating Voltage Ranges for AC-Powered Equipment ...................................... 1-4
Color Codes for AC Wire ........................................................................................... 1-6
Summary of Minimum Lab Testing Requirements for DC Power Equipment 1-11
Color Codes for Equipment Visual Indicating Lights ......................................... 1-13
Typical Battery Disconnect Sizes for Long-Duration Flooded Lead-Acid ....... 3-19
3-2 Typical Battery Disconnect Sizes for Ni-Cd Batteries .......................................... 3-19
Typical Battery Disconnect Sizes for Long-Duration VRLAs ............................. 3-20
Recommended Voltage Operating Windows for Line-Powered Equipment .... 4-4
Resistance and Ampacity of Common Sizes of OSP Copper Pairs ..................... 4-5
Bus Bar Ampacity for Single Bars ............................................................................. 9-9
Bus Bar Ampacity for 2-4 Bars per Polarity in Parallel ....................................... 9-10
Bus Bar Ampacity for 5-12 Bars per Polarity in Parallel ..................................... 9-11
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CONTENTS (Continued)
Tables Page
Power Wire Ampacities ........................................................................................... 9-12
12-1 Wire and Protector Sizing for -48 VDC Powered Lighting Circuits .................. 12-2
13-3 Reduced Character and Overhead Bitstream TL1 Alarm Condition Types .. 13-14
13-4 DMS ™ 10 Pre-Assigned Scan Point Messages for Power Plants ....................... 13-15
13-5 DMS ™ User-Assignable Scan Point Power Standards for NMA ® .................... 13-17
13-6 Power Messages for Integrated DMS ™ -1 Urban ................................................. 13-20
13-7 NMA ® Power Messages for Nortel Remote Switches in RTs ........................... 13-22
13-8 5ESS ™ Standard Power Messages for Hosts ....................................................... 13-23
13-9 5ESS ™ Standard Power Messages for Remotes .................................................. 13-24
13-10 5ESS ™ User-Assignable Scan Point Power Message Standards ....................... 13-24
13-11 Ericsson AXE ™ Standard Power Alarm Messages for NMA ® .......................... 13-27
13-12 TL1 Query Messages for Power ............................................................................ 13-31
13-13 Typical Output Voltage Settings ........................................................................... 13-33
13-14 Battery Plant Voltage Alarm Set Points ............................................................... 13-35
13-15 Converter Plant (no batteries on output) Voltage Alarm Set Points ............... 13-36
13-16 VRLA Temperature Compensation and Recharge Current Limit Settings .... 13-37
13-17 Power Temperature Alarm Set Points ................................................................. 13-38
13-18 Current Thresholds ................................................................................................. 13-39
13-19 Battery Ohmic Thresholds ..................................................................................... 13-40
13-20 AC Voltage Thresholds .......................................................................................... 13-41
13-21 Fuel Alarm Thresholds ........................................................................................... 13-41
13-22 kW/kVA or AC Load Current Capacity Thresholds ........................................ 13-42
13-23 Typical Power Alarm Points for Smaller Sites Without Engines ..................... 13-42
13-24 Typical Power Alarms for Small Sites with Only 4 Overhead Bits ................. 13-43
13-25 Typical Power Alarms for Small Sites with Only 2 Overhead Bits ................. 13-43
13-27 SNMP Power Alarm Messages used in CenturyLink ™ ..................................... 13-45
Figures Page
A Powering Scheme for a Central Office ................................................................. 2-1
Typical Outside Plant Equipment Enclosure Power Scheme ............................... 2-2
Typical Radio Site Power Scheme ............................................................................ 2-2
3-1 Typical Arrangement of Cables for a Flooded Battery Stand ............................. 3-17
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Table Of Contents
CONTENTS (Continued)
Figures Page
Minimum Dimensions for a Bus Bar above Flooded Battery Stands ................ 3-17
30-Ampere Cable Hardwired to Single-Phase Engine-Alternator ..................... 7-34
30-Ampere Cable to Single-Phase Engine-Alternator Receptacle ..................... 7-35
30-Ampere NEMA ® L14-30P Locking Connector Pin Configuration ............... 7-35
100-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connector, Cable
Hardwired to Single-Phase Engine-Alternator .................................................... 7-36
100-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connectors, Cable to
Single-Phase Engine-Alternator Receptacle .......................................................... 7-36
100-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connector, Cable
Hardwired to Three-Phase or Single/Three-Phase Engine-Alternator ............ 7-37
100-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connectors, Cable to Three-Phase or Single/Three-Phase Engine-Alternator Receptacle ............. 7-37
7-8 100/200-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve Receptacle
Front-View Pin Configuration ................................................................................ 7-38
7-9 100-Ampere IEC 60309 Orange Plastic-Sleeve 4-Pin Connector, Cable
Hardwired to Single-Phase Engine-Alternator .................................................... 7-38
7-10 100-Ampere IEC 60309 Orange Plastic-Sleeve 4-Pin Connectors, Cable to Single-Phase Engine-Alternator Receptacle ..................................................... 7-39
7-11 IEC 60309 Orange Plastic-Sleeve 100 Amp Receptacle Pin Configuration ....... 7-39
® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connector, Cable
Hardwired to Single-Phase Engine-Alternator .................................................... 7-40
® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connectors, Cable to Single-Phase Engine-Alternator Receptacle ..................................................... 7-40
® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connector, Cable
Hardwired to Three-Phase or Single/Three-Phase Engine-Alternator ............ 7-41
® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connectors, Cable to Three-Phase or Single/Three-Phase Engine-Alternator Receptacle ............. 7-41
9-1 Batteries to Main Distribution Voltage Drops Via MTBs ...................................... 9-5
9-2 Batteries to DC Plant Voltage Drops Where There is No Centralized Shunt .... 9-5
9-3 Power Plant Distribution to BDFB Voltage Drops ................................................. 9-6
9-4 PBD to BDFB (via Remote A/B PBDs) Voltage Drops .......................................... 9-6
9-5 Power Plant to BDFB (via a Single Remote PBD) Voltage Drops ........................ 9-7
9-6 BDFB to Equipment Bay Voltage Drops .................................................................. 9-7
9-7 Power Plant Distribution Direct to Equipment Bay Voltage Drops .................... 9-8
9-8 Bus Bars with Bar Width Vertical and Spaced ≥ Bar Thickness ........................... 9-8
9-9 Bus Bars run Flat ....................................................................................................... 9-13
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CONTENTS (Continued)
Figures Page
9-10 Vertically Run Bus Bars ............................................................................................ 9-13
911 Typical Mounting of a Bus Bar above PDFs and Battery Stands ....................... 9-19
9-12 Splitting the Voltage Drop when a Top-of-Bay Fuse Panel Serves
Equipment More Than One Bay Away ................................................................. 9-22
9-13 BDFB Fuse Assignment Label ................................................................................. 9-25
9-14 Typical Layout of BDFB Fuse Panels ..................................................................... 9-26
9-15 Typical Layout of 2 Load 600 Ampere BDFB........................................................ 9-27
9-16 Typical Layout of 4 Load 400 Ampere BDFB........................................................ 9-28
9-17 Typical Return Bus Bar Mounting for a 7’ BDFB (View A-A) ............................ 9-29
9-18 Typical Return Bus Bars Mounting for a 7’ BDFB (View B-B) ........................... 9-30
9-19 Load and Embargo Labels for BDFBs .................................................................... 9-31
9-20 Example of Bus Bars (Term Bars) above a Battery Stand .................................... 9-32
9-21 A Battery Return Bus Bar above a BDFB ............................................................... 9-33
9-22 Chandelier Hot Side Main Terminal (Term) Bar .................................................. 9-33
9-23 Chandelier Return Side Bar ..................................................................................... 9-33
9-24 Example of a Remote Ground Window ................................................................ 9-34
9-25 Example Main Return / Ground Window MGB Bar .......................................... 9-34
9-26 Example of Sandwiched Terminations .................................................................. 9-34
Forms
821A Power Room Lighting Test and Acceptance Checklist ....................................... 15-5
821B Alarm and/or Power Monitor/Controller (PSMC) Test and
Acceptance Checklist ................................................................................................ 15-6
821C BDFB, Power Board, or Fuse Panel Test and Acceptance Checklist .................. 15-7
826B Transfer System and AC Service Entrance Test and Acceptance Checklist ... 15-16
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Table Of Contents
CONTENTS (Continued)
Forms Page
826C Fuel Tank, Fuel System, and Fuel Monitor Test and Acceptance Checklist .. 15-17
828B Power Distribution Bus Bar Test and Acceptance Checklist ............................ 15-20
Power Area Floor Plan Test and Acceptance Checklist .................................... 15-21
829B Power Documentation Test and Acceptance Checklist ..................................... 15-22
841 BDFB/PBD Panel Fuse/Breaker Assignment Record ....................................... 15-24
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Chapter 1
General Requirements
Chapter and Section
1.
CONTENTS
Page
General Requirements and Definitions .................................................................. 1-1
1.1 General ............................................................................................................. 1-1
1.2 Reason For Reissue ........................................................................................ 1-2
1.3 Requirement Applicability ........................................................................... 1-2
1.4 AC Requirements ........................................................................................... 1-3
1.4.1 AC Surge Suppression ................................................................ 1-7
1.5 Generic Technical Requirements ................................................................. 1-7
1.6 NEBS ™ Requirements .................................................................................. 1-10
1.7 Generic Alarming Requirements ............................................................... 1-12
Tables
1-1 Operating Voltage Ranges for AC-Powered Equipment ...................................... 1-4
1-2 Color Codes for AC Wire ........................................................................................... 1-6
1-3 Summary of Minimum Lab Testing Requirements for DC Power
Equipment .................................................................................................................. 1-11
1-4 Color Codes for Equipment Visual Indicating Lights ......................................... 1-13
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1. General Requirements
1.1 General
Chapter 1
General Requirements
This section is intended to provide general requirements that apply to all of the units of the document, which follow.
All power equipment shall be Manufactured, Engineered, and Installed in accordance with the following:
• CenturyLink ™ Technical Publications
— Detail engineering for CenturyLink ™ sites shall meet all the standards stated herein;
— CenturyLink ™ standard configuration documents; and
— CenturyLink ™ fire and life safety practices.
• Telcordia ® Recommendations
• Alliance for Telecommunications Industry (ATIS) documents
• American National Standards Institute (ANSI) standards
• Institute of Electrical and Electronics Engineers (IEEE) standards
• Federal Communications Commission (FCC) documents
• National Electrical Code (NFPA ® 70)
• Underwriters Laboratories (UL ® ) Requirements
• RUS standards, except as modified by this document
• Department of Labor - Occupational Safety and Health (OSHA) Standards
• Federal, State, and local requirements including, but not limited to, statutes, rules, regulations, and orders of ordinances imposed by law.
All power equipment used by CenturyLink™ shall have passed through the
CenturyLink ™ Product Selection procedure.
Any changes made to requirements in this Technical Publication 77385 become effective as of the publication date of the revision, going forward.
CenturyLink ™ prefers that all end equipment carrying Network traffic be powered by nominal -48 VDC power (the equipment shall be capable of accepting voltages at least from -42.65 to -56 VDC). The primary power plant is typically a -48 VDC plant, although in some microwave radio sites, the primary plant may be -24 VDC.
1-1
Chapter 1
General Requirements
PUB 77385
Issue K, July 2015
While some modern equipment does use the -48 VDC directly, much of the equipment needs to convert it to other nominal DC voltage levels, such as 3.3, 5, 9, 12, 24, 130, or
190 V. This is usually done on a power supply card in the shelf with on-board “brick” chip DC-DC converters. However, there are sometimes needs for bulk feeds to equipment at nominal +24 V, -24 V, -130 V, ±130, or ± 190 VDC. In these cases, a large battery plant at the appropriate voltage can be used, or a bulk DC-DC converter plant
(see Chapter 4 for converter plant requirements) can be placed and powered from the primary -48 or -24 VDC plant.
If there is equipment carrying Network traffic that needs an uninterruptible AC source, it most preferably would use a feed from an inverter plant (see Chapter 5 for requirements for inverter plants). In the case of very large uninterruptible AC needs, or
Customer Premises installations (see Technical Publication 77368), a commercial UPS may be used (see Chapter 6 for requirements for UPS systems). (For further information on AC requirements, see Section 1.3.)
The use of a blowtorch, acetylene torch, fiber fusion splicing equipment, or any open flames and/or sparks are not permitted in any CenturyLink ™ battery room, per
CenturyLink’s safety standards and the Fire Codes.
1.2
Reason For Reissue
This document is primarily being reissued to clarify power plant sizing rules, clarify minor wiring language, and merge combined company (Qwest, CenturyTel, Embarq,
LightCore, etc.) power standards.
1.3
Requirement Applicability
The following applies:
SHALL
MUST
When this designation is used in a requirement, it denotes a binding requirement (not optional) due to fire, life, or safety reasons.
When this designation is used in a requirement, it denotes a binding requirement, but does not involve fire, life, or safety.
WILL or
SHOULD
When this designation is used in a requirement, it denotes a condition that is a CenturyLink ™ preference.
Note that regardless of the collocation rules listed in this document, if an individual
CLEC ICA has differing language, the ICA is the governing document.
1-2
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1.4
AC Requirements
Chapter 1
General Requirements
There are three types of AC loads that may be required within a CenturyLink ™ telecommunication site.
• Protected Loads — protected loads will use either an inverter (Chapters 5) or
UPS (Chapter 6). If the inverter is operated in DC-preferred mode, or the UPS is
“on-line” (aka double-conversion), there is no switching time (the power supplied is truly uninterruptible). If the inverter is operated in AC-preferred mode, or the UPS is line-interactive, the static transfer switch in the inverter/UPS will switch to backup power during a power “event” in less than 4 milliseconds.
• Essential Loads — those telecommunications and building AC loads that must operate during prolonged loss of commercial AC power. These loads are normally run off an on-site, auto-start, auto-transfer standby engine-alternator
(Chapter 7). An example of an essential load is air-conditioning in a larger building in a hotter climate
• Nonessential Loads — those that can experience long periods of commercial power interruption without needing some form of backup. Generally, these loads are not switch-able to the standby source. Most building lighting qualifies as non-essential loads, for example. In smaller buildings, it may not be economical to provide two separate essential and non-essential buses. In those, buildings, if they are equipped with an on-site engine, generally all the loads are on the essential bus.
All installed AC equipment will be provided with adequate working space as defined in the National Electrical Code (NFPA ® 70), Article 110.26.
AC equipment shall be capable of operating without damage from any input source with the following characteristics:
• The equipment shall be operational from a 60-Hertz (Hz) source ± 10%.
• Voltage Limits — The limits shown in Table 1-1 are consistent with range B utilization limits of American National Standard Institute (ANSI) Voltage Rating for Electrical Power Systems and Equipment, and apply to sustained voltage levels:
1-3
Chapter 1
General Requirements
Table 1-1 Operating Voltage Ranges for AC-Powered Equipment
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Phases
1
1
1/3
3
Nominal
Voltage
120
220/240
208/240
277/480
Voltage Limits minimum maximum
106
184
184
424
127
254
254
508
AC circuits shall use THHN or THWN type wire, color-coded in red, blue, black, white, yellow, brown, orange, and green per Table 1-2. THHN and THWN should not be used for DC applications except where they are run in conduit or within a bay where they are protected from abrasion or coldflow at impingement points (CLECs are exempt from this requirement for their runs after the point where CenturyLink ™ has dropped DC power to them). The use of colored tape on both ends of the wire is acceptable for AC wire color coding, except that 6 AWG or smaller neutral conductors require a continuous white or natural gray outer finish along their entire length. All AC wire approved for CenturyLink-owned building applications shall be run in conduit, raceway, or metallic enclosure. Wire applications are defined in Chapter 9.
All AC neutrals shall be sized at the same size as the phase conductors, at a minimum.
AC wires used in RT/Prem applications do not have to be run in raceway or conduit if they are cords terminated in a NEMA ® Twist-Lock plug. These wires must be fire retardant Hypalon coated or polyethylene (XLP-USE-2, or EPR-USE-2, or RHH/RHW-
2).
AC power wire shall be copper conductor only within buildings owned by
CenturyLink. The AC feeds from the house service panel (HSP) to the Power
Distributing Service Cabinets (PDSCs) serving the rectifiers shall be dual feed for DC plants rated 2400 Amps and larger and/or where the AC service entrance size is 500 A or larger. One dual feed PDSC or two separately fed PDSCs will meet this requirement
(if the separately fed PDSCs are served through step-up or step-down transformers, there should be one transformer for each PDSC). Attempt to evenly split the rectifier loads among the PDSCs when there are multiple PDSCs. PDSCs can be either standalone, wall mounted, or at the top of a rectifier bay. The PDSC feeds from the house service board shall be sized to the capacity of that PDSC, (i.e., a 600-Ampere PDSC shall be sized and fed at 600 Amperes). A PDSC shall be dedicated to that rectifier line-up which it is serving.
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Chapter 1
General Requirements
Rectifier circuit breakers shall be sized to the rectifier manufacturers’ recommendation.
PDSCs only need to be equipped with breakers for existing rectifiers. Future circuit breakers may be added when rectifiers are added to the power plant. The cabinet and the breakers will be rated for the available fault current (kAIC). (The fault current available at that point may need to be calculated by a Professional [P.E.] Electrical
Engineer.) PDSCs for plants with an ultimate capacity of at least 2400 Amps DC should be rated at 600 Amps AC (and the feed to them should generally be at 600 Amps unless the entire site service entrance is not rated that high). In smaller sites the PDSC can be rated as small as 100 Amperes, or some smaller sites may not even have a PDSC, but will have the rectifiers fed from the primary AC distribution panel directly. Rectifiers fed from secondary AC distribution panels can only be fed from PDSCs dedicated to rectifiers. RT Sites that use a power pedestal for AC should be sized per Chapter 11.
All AC cabling in telecommunications equipment areas, (including power rooms), will be enclosed in conduit, or approved cable raceway. Armored power cable (type AC, aka BX) or Liquid-Tite™ will only be used in special applications where rigid conduit is not practical and as specified by the NEC ® (see Chapter 9 of Technical Publication 77350 for rules governing the use of AC conduit types). Flexible metal conduit shall not be used ever in power rooms per NEC ® Article 348.12(3), unless it is type MC.
All rigid, EMT and metallic liquid tight flexible conduit runs shall be made with steel compression or steel threaded type fittings, steel couplings, and junction boxes, unless they are larger than 1¼” diameter; in which case, set screw fittings are allowed, but not preferred.
No PVC conduit or tubing shall be used of any kind indoors or exposed outdoors. It may be used for underground or concrete pour applications for AC service.
Horizontal runs of conduit across concrete pads outdoors must be EMT or rigid metal.
AC feeds from the raceway or junction box to the rectifier/charger must be run in either thin wall or Liquid-Tite™ conduit. Flexible conduit shall not be installed on cable racks.
Collocators in CenturyLink-owned space may have CenturyLink-provided convenience outlets in their space or bay (depending on the ICA, there will usually be three in a cage, for example). These outlets are only for temporary power to test equipment and the like, and not for permanent powering.
If a collocator desires a permanent AC power feed, they may order standard nonessential AC, essential AC (backed by an engine, but interruptible during transfer events), or uninterruptible AC feeds (typically provided by a CenturyLink ™ inverter fed from a CenturyLink ™ Local Network DC plant); or, with CenturyLink ™ permission, the customer may install an inverter in their space fed from CenturyLink ™ DC feeds.
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A customer-provided inverter must meet NEBS ™ Level 1 (see Section 1.6) for NEBS ™ spaces, and have its neutral and ground wired in accordance with Tech Pub 77355. For non-NEBS ™ spaces, the inverter must be Listed, and if not caged must be separated from CenturyLink equipment by at least 6 feet if it is not NEBS ™ Level 1. If the customer desires a maintenance bypass circuit for their inverter(s), they must order a permanent non-essential or essential AC feed from CenturyLink ™ .
A collocator is not allowed to install any rechargeable batteries (or UPS containing them) in their space inside a CenturyLink ™ facility. A collocator is also not allowed to place flywheels in their space. They may install these items in an adjacent collocation.
For adjacent collocation (CLEC leasing property from CenturyLink in a separate CLECowned structure), the CLEC may procure their own AC feed from the electric utility, or get CenturyLink ™ -provided AC via one of the circuit types previously listed. While the
CLEC can avail themselves of a generator-backed essential AC feed, they aren’t allowed to install a permanent engine on CenturyLink ™ property. When an adjacent collocation receives AC power from a CenturyLink ™ structure, the AC must have an SPD where it leaves the structure, and the CLEC would be wise to use a TVSS on their end as well.
Table 1-2 Color Codes for AC Wire
Nominal Voltage Phase/Line/Leg Color
240/120
208/120 Y
240/120 Δ
240/120
208/120 Y
240 Δ
208/120 Y
240/120 Δ
240/208 Δ
480/277 Y
480/277 Y
480/277 Y
1
A
2
B
C
B
A
C
Black
Red
Blue
Orange
Grounding
120/208/240
277/480
Neutral
Brown
Yellow
Green or
Green w/yellow stripe or bare Copper
White or Gray
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1.4.1 AC Surge Suppression
Chapter 1
General Requirements
Transient Voltage Surge Suppressors (TVSS) [aka Surge Protection Devices (SPDs)] must meet and be Listed to the latest edition of UL ® 1449, the ANSI/IEEE C62 series document, and NEC ® Articles 280 for surge arrestors over 1000 V, or 285 for SPDs. It is also preferable that TVSS/SPDs and surge arrestors be tested to NEMA ® LS 1.
The SPD shall be as close as possible to the AC source (18 cable inches or less with no bends in the wire is preferred, with a maximum of 4 feet except when not physically possible). Install the SPD on the load side of the AC entrance unless also
Listed and rated as a “Surge Arrestor”. (If installed on the line-side, it is replaced
“hot”, so that placement is discouraged, especially when CenturyLink ™ doesn’t own the transformer serving the building). Install SPDs per the manufacturer.
If the SPD is connected directly to the hot buses, it must have a minimum surge rating of 69 kAIC. If connected through breakers (disconnects are preferred because it allows replacement without de-energizing the site), the breakers should be a minimum of 30 Amps (preferably 60 Amps or larger).
Downstream TVSSs are generally discouraged as unnecessarily costly unless they come as an integral part of the equipment (such as in a power strip or PDU), or are used to solve a specific proven problem.
For SPDs in COs, radio sites, or large Data Centers, the minimum kA suppression rating is 200 (400 or more preferred), with a minimum rating of 5000 J. These larger site TVSSs should provide common and transverse mode suppression. For TVSS in
RT locations or fiber regen huts, minimum suppression is 100 kA (200+ preferred), with a minimum rating of 2000 J (3000+ preferred). SPDs used on 208 or 240 VAC sites should not have a breakdown rating > 600 V ( preferably 400-500 V), while those for nominal 480 VAC should have a breakdown typically from 800-1000 V.
1.5 Generic Technical Requirements
All power equipment must conform to American National Standards Institute (ANSI) requirements, and shall be Listed to the appropriate UL ® (Underwriters Laboratory) standard (if no other standard applies, UL ® 1950/60950-1 probably does). Power components (rectifiers/chargers, controllers/monitors, inverters, UPS, converters, engine-alternators, transfer systems, generator set plugs, AC power cabinets, and power pedestals) shall meet the requirements of the National Electrical Code.
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Powering equipment with non-metallic components must be fire-retardant rated as
UL ® 94-V0 and have a minimum Limiting Oxygen Index (LOI) of 28% or greater.
Grounding cable (that is not manufacturer internal shelf and intra-bay wiring) in all larger sites (including all COs) shall be green in color, green with yellow stripe, or bare; and be in accordance with CenturyLink ™ Technical Publication 77355.
All active electronic devices shall be solid-state.
All relays will be solid-state or provided with dust covers.
Protection devices can be either fuses or circuit breakers. All protection devices shall be sized at a minimum of 125% of the peak load and rated for the available fault current
(kAIC) which meets or exceeds the maximum available fault current at that point in the system. All fuses or circuit breakers must be AC rated for AC circuits, and DC rated for
DC circuits. One spare fuse shall be provided for every 5 fuses ordered.
Fuses and breakers feeding CenturyLink ™ equipment must be coordinated from a size and time-current curve perspective to increase the chances that the downstream protector is the first to blow/trip. This does not apply if the relationship is 1-to-1 (in other words, the upstream fuse or breaker only feeds 1 downstream fuse or breaker).
Fuse blocks and circuit breakers shall be front accessible, and labeled to indicate their
Ampere rating and circuit assignment (frame/shelf). Circuit breakers shall be labeled according to the NEC. When circuit breakers are mounted horizontally, the “UP” position shall be “ON”. All circuit breakers should be equipped with shields to prevent accidental tripping.
Renewable link and H type fuses are not acceptable for use. All internal circuits shall be protected with fuses mounted in a “dead front” fuse holder. Internal fuses must be easily accessible. Each fuse shall be provided with a blown fuse indicator connected to an alarm-indicating lamp on the control panel. All power semiconductor circuits shall be fused using KAA type fuses to prevent cascading or sequential semiconductor failures. All electrolytic capacitors shall be fused. A maximum of two capacitors shall be protected by one fuse.
Parallel fusing (even with circuit breakers) is not allowed, per NEC ® Article 240.8.
If circuit breakers are used, they shall be thermal-magnetic and trip free. Contacts shall not be capable of being manually held closed during an overcurrent condition.
All power semiconductor circuits shall be fused to prevent cascading or semiconductor failures.
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Insulating materials in arcing paths of contacts, fuses, etc. shall be non-tracking type.
Insulating material that independently supports combustion, or ignites from a spark, flame, or heating shall not be used. The combustion products of insulating materials shall not combine with normal air to form acid, toxic, or other deleterious products.
All DC runs under a raised floor or in a ceiling that is also used as an air plenum must be in a plenum rated raceway, metal conduit, or metallic liquid tight flexible conduit; or must be plenum-rated or MI or MC type cable.
If forced air-cooling is used to keep power components cool the blower motors shall be equipped with sealed ball bearings, (this does not pertain to the HVAC system).
Blowers shall be redundant. A failure of a blower unit shall generate an alarm. All air inlet and exhaust openings shall be protected with expanded metal guards.
The structural members of power equipment shall not carry or conduct load currents.
Ferrous materials shall not be used for current carrying parts.
Metal parts, unless corrosion resistant shall have a corrosion protection finish. Ferrous parts not required to meet an appearance criteria shall have zinc plate, cadmium plate, or an approved equivalent finish applied. The minimum thickness of the finish shall be
0.0002 inches, plus a chromate treatment. When dissimilar metals are used in intimate contact with each other, protection against electrolysis and corrosion shall be provided.
This protection may be metal plating, or use of a suitable insulating material (including a thin film of anti-oxidant if electrical conductivity needs to be maintained).
Nut, bolts, and screws for connection and mounting should be grade 5 or equivalent.
Wire used for carrying load current shall be copper conductor only. Wire subject to hinged action shall be of the stranded type.
Copper crimp connectors (Listed for the application and applied with tools they were cross-Listed to), wire wraps or latching plugs shall be used for all DC wire connections to CenturyLink ™ CO equipment shelves that would carry lifeline traffic (it is also encouraged for RT cabinets and Prems, but may not always be possible in small DC plants that take up 1 or 2 RUs). Use anti-corrosion compound on power connections.
Bus bar shall be of 95% hard-drawn copper (UNS-C11000 or ETP-110).
All individual components of power equipment should be designated. Each Test Point must be accessible and assigned a designation starting with TP1. Designations shall be shown on the schematic drawing, on or adjacent to the point being designated.
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Equipment that provides power (i.e. power plants, converters, inverters, BDFB, miscellaneous fuse panels, etc.) shall be designated as follows:
• Fuse or circuit breaker panels as panels;
• Rectifiers with a G and a numeric designation (G-01, etc.), and;
• Rectifier shelves as a shelf.
1.6 NEBS ™ Requirements
The requirements of this section only apply to CenturyLink ™ equipment in NEBScompliant equipment spaces. NEBS ™ certification and compliance of CLEC equipment placed in CenturyLink facilities is the responsibility solely of the CLEC.
The supplier of power equipment going into NEBS-compliant CenturyLink ™ telecommunications areas shall meet the requirements of Telcordia ® GR-1089-CORE, and GR-63-CORE, as the GRs pertain to its equipment. Pertinent requirements and
NEBS ™ compliance are determined by the third party test lab for equipment supplied to
CenturyLink. Depending on the technology, CenturyLink ™ Product Selection may also require compliance to other Telcordia ® GRs (many of them in the NEBS ™ family) relevant to the technology and the environment into which the equipment may be placed.
The supplier must test to the GRs as required by CenturyLink. CenturyLink ™ requires that all NEBS ™ tests be performed at an independent third party test facility. These test facility must be accredited as part of a laboratory accreditation program sponsored by one of the following, American Association for Laboratory Accreditation (A2LA),
National Voluntary Laboratory Accreditation Program (NVLAP), National Recognized
Testing Laboratory (NRTL), and Underwriters Laboratories. Test facilities must be certified for those fields of accreditation that encompass NEBS ™ requirement.
CenturyLink ™ cannot and does not certify testing facilities. CenturyLink ™ will however accept test data from a supplier's testing facilities provided it is accredited to perform the test and observed by a member of another accredited laboratory as defined herein.
CenturyLink ™ will not accept test reports written by the supplier or a supplier's interpretation of a test lab report. CenturyLink ™ will only accept test reports written by the independent test lab performing the work or by the representative of the observing third party lab. All test reports must be written on the letterhead of the lab.
All components shall be tested as a system. However, if individual components or subsystems have been tested a letter from the testing lab stating that the assembly of the unit or subsystems into the system will not change the NEBS ™ data will be acceptable.
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Note that wire and connectors are not tested to NEBS, but do have to be Listed.
Equipment placed in non-Network areas (such as AC equipment or an engine in their own room) also do not have to be NEBS-tested, but must be Listed. Note also, that only equipment to be used in NEBS ™ Earthquake Zones 3 and 4 must be tested to Zone 4
(equipment for use in COs in Zones 0-2 need only be tested to Earthquake Zone 2 criteria). Not all CenturyLink ™ network equipment spaces/sites are NEBS-compliant.
As a general rule of thumb, if the Network equipment area has an automatic fire suppression system, the equipment in it is not required to be NEBS-compliant.
Note that the lab testing requirements listed in Table 1-3 apply to only a sample of the equipment (not every piece leaving the factory must be tested). Note also, that these are the minimum requirements. It would be desirable, for example, if Customer Premises and CEV DC power equipment that are to be placed in Earthquake Zone 3 or 4 were tested to those criteria, but it is not absolutely required.
Table 1-3 Summary of Minimum Lab Testing Requirements for DC Power Equipment
Requirement
Listed
NEBS ™ 1
Hardened
NEBS ™ 2
EMI NEBS
ESD NEBS
™
™
3
3
Earthquake
NEBS
NEBS ™
™ 3
Other
Site Type
NEBS ™ CO CEV/C, UE, hut RT Cab
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Prem
X
While Listing to a UL ® standard denotes that the product is safe from a fire-safety perspective, it does not necessarily mean that the product will continue to work after being subjected to certain types of abuse. While some NEBS ™ Level 1 requirements are similar to UL ® safety tests, and can be done by the same lab, NEBS ™ typically stresses equipment far beyond what UL ® specifications require.
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A detailed summary of NEBS ™ Levels 1, 2, 3, and “Other” requirements is given in
Telcordia ® SR-3580; however the Levels generally mean:
• Equipment complying with NEBS ™ Level 1 is not harmful to other nearby equipment. It will not emit EMI harmful to other equipment when its doors/shields are in place, will not sustain flame, will safely conduct internal short circuits out through the safety ground system, is Listed to the appropriate
UL ® standard, will withstand low-level lightning and AC power transients, and has its higher voltages shielded from accidental contact, and properly labeled.
• Equipment complying with NEBS ™ Level 2 (in addition to not being harmful to nearby equipment, including with its EMI shields/doors open), will withstand some mild abuse; such as Zone 2 earthquakes and vibration, some temperature and humidity variation, some airborne contamination (including mild corrosive exposure), mild ESD while in-service, radiated and conductive/inducted EMI when its shields/doors are closed / in place, higher level lightning and other AC power transients, incoming conducted emissions on power and signaling leads, and mild DC overvoltage.
• Equipment complying with NEBS ™ Level 3 meets the highest level of robustness to abuse (in addition to meeting all the Level 1 and 2 criteria). Additional testing includes: short-term wider-range temperature and humidity fluctuations; high terrestrial altitude operation; reliability after transportation, storage, and handling abuse; Zone 4 earthquake immunity; ESD immunity during poor-ESD maintenance handling; immunity to electrical fast transients; minimal radiated or conducted EMI with the shields removed or doors open; incoming conducted emissions on data leads; and protector coordination.
• “Other” NEBS ™ requirements include: space and weight, equipment air filtration (if needed), heat dissipation, acoustic noise, etc.
1.7 Generic Alarming Requirements
All provided alarms will have a set of dry contacts so that the alarm can be remoted.
The connecting point for these contacts will be easily-accessible. All analog monitoring points within the equipment will be equipped with terminal strip access for attaching remote monitoring devices. The connecting point for analog monitoring points will be located near the alarm connecting points and be easily accessible.
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All DC circuit breakers shall generate an alarm signal when in the tripped state
(electrical or midtrip type breakers). Battery disconnect breakers shall also generate an alarm when turned off (mechanical trip). For other breakers, whether to use breakers that generate an alarm in the off state (mechanical and electrical trip) is a decision left up to the Engineer.
The status indicators and alarm outputs shall be in the form of visual indicators in the plant (preferably lighted); and electrical signals for alarm sending circuits, and for connection to the office alarm system. The visual alarm and status indication system shall have its own dedicated power supply circuit, operating from the plant voltage.
This supply shall have an overcurrent protection device that will send a visual alarm when it has operated, or power has been removed from the "control and status" system.
Color-Codes for visual equipment indicators will be as follows:
Table 1-4 Color Codes for Equipment Visual Indicating Lights
Color
Green
Amber,
Orange, or Yellow
Red
White
Description
Indicates proper operation of the system or equipment.
MINOR/PRELIMINARY — indicates an abnormal operating condition within the power system or equipment that requires attention, but power service to the load is not currently affected.
MAJOR/CRITICAL indicates a failure that currently affects power service to the load, or a failure, which may mask an alarm, associated with a service-affecting problem.
Signify conditions that have none of the above connotations of red, yellow, or green.
The alarm output for the office alarm system may have multiple outputs for each alarm
(e.g., one for an existing local audible alarm system, one for existing local visual alarm indications, and one for a remote alarm system). If only one set of contacts exists for each alarm, they can be wired to all 3 systems (audible, visual, remote) if necessary
(local audible and visual systems are much less common now than they once were). In some cases, the power equipment may have its own audible and visual alarm system.
The contacts for the alarms shall be capable of supporting 60 VDC and 0.5 Amperes, and shall be electrically isolated from each other and the frame ground.
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It is desirable that an Alarm Cut-Off key or button (ACO) be provided to inhibit the office audible alarm function, without interfering with the visual or remote alarm systems.
A method shall be available to actively test all status indicators to verify they are in working condition.
Distribution fuse fail alarms for BDFBs (classified as Major in criticality) in the IOF areas must be run to the local e-telemetry device. Alarming miscellaneous fuse panels remotely may be optional depending on the legacy CenturyLink ™ company, since the served equipment may signal the loss of power. The criticality of the equipment served may also play into the decision as to whether or not to alarm a miscellaneous fuse panel remotely. These alarm leads must be run in the switchboard cable rack.
Power alarm and monitoring leads that are within the power area only may be run on the side of the cable rack, on the horns, or on the hangers. Waxed 9-cord shall be used for securing these leads. Clips or wire ties are not acceptable for securing the alarm wires in this application in a Central Office.
Engine alarm leads (or other power alarm leads from non-traditional equipment areas without cable racking) may be run in conduit (inside the engine room, those leads must be run in conduit).
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Chapter 2
DC Power Plants, and Rectifiers
CONTENTS
Chapter and Section Page
2.
Figures
DC Power Plants and Rectifiers ............................................................................... 2-1
2.1 Overview ......................................................................................................... 2-1
2.2 General DC Power Plant Requirements ..................................................... 2-1
2.3 Charging Equipment (Rectifiers) and Their Controller ........................... 2-6
2.4 Engineering Guidelines ................................................................................. 2-9
2.4.1 Example of Proper Calculation and Usage of List 1 and
List 2 Drains ................................................................................ 2-12
2.5 Power Board Panel and Fuse Numbering for New Plants .................... 2-16
2.6 Conventional Controller ............................................................................. 2-17
2-1 A Powering Scheme for a Central Office ................................................................. 2-1
2-2 Typical Outside Plant Equipment Enclosure Power Scheme ............................... 2-2
2-3 Typical Radio Site Power Scheme ............................................................................ 2-2
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2. DC Power Plants, and Rectifiers
2.1 Overview
This unit covers requirements for DC power plants and rectifiers used within telecommunications facilities.
Chapter 2
DC Power Plants, and Rectifiers
2.2 General DC Power Plant Requirements
One powering scheme for a Central Office is shown in Figure 2-1. There are many other possible configurations. A characteristic powering scheme for an Outside Plant equipment enclosure (e.g., CEV, cabinet, Customer Premises site, etc.) is shown in
Figure 2-2. Figure 2-3 shows a characteristic-powering scheme for a radio site.
Figure 2-1 A Powering Scheme for a Central Office
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Commercial
AC
Portable
Engine
Plug
Manual
Transfer
Switch
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Optional PSMC CL i f i e
R e c t r s
Temperature compensation
Power
Board
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
Battery
Disconnects
-
-
-
-
-
-
-
-
-
-
-
-
-
VRLA or Ni-Cd
Batteries
Figure 2-2 Typical Outside Plant Equipment Enclosure Power Scheme
E q p t
2-2
Figure 2-3 Typical Radio Site Power Scheme
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The principle components of the power distribution plant are:
Chapter 2
DC Power Plants, and Rectifiers
• LOCAL AC POWER DISTRIBUTION —, which includes conduit, cabling, fasteners and protective equipment. The PDSC is an Essential AC panel that feeds the rectifiers.
• CHARGING/RECTIFIER EQUIPMENT — consists of rectifiers and associated equipment to convert AC power to DC power at voltages suitable for
CenturyLink ™ applications.
• TEMPERATURE COMPENSATION — and/or charge current limiting may be separate or an integral part of the charging equipment for use with VRLA batteries. Temperature compensation measures battery temperature(s), and adjusts the plant voltage accordingly to limit recharge current to the batteries thereby helping to reduce the risk of thermal runaway. The temperature sensing is preferably done once per string on the most negative cell post of that string; and the control of the power plant float voltage is adjusted based on the highest battery temperature measured. Charge Current Limiting simply limits the available charge current to the batteries (either to prevent thermal runaway or prevent overload of the rectifier current limiting circuitry in the case of super™/ultra™ capacitors).
• STORAGE BATTERIES — provide a source of DC power to the equipment when
AC is not present, until the AC can be restored. They may also provide filtering of the rectifier output for some older types of rectifiers where the filtering wasn’t integral to the rectifier output.
• DISCHARGE BAYS — contain the control and output circuits; including fuses and/or circuit breakers, shunts, meters, bus bar, alarm circuits and other equipment necessary for plant operation. May be the same as the PBDs described below.
• BATTERY DISTRIBUTION BOARD (BDB), or POWER BOARDS (PBDs) — is the primary power distribution within the DC plant (the originating PBD includes the controller). It is powered directly from the batteries and rectifiers. In addition, it contains the primary cable protection equipment, and shunts. The
BDB may also contain meters and alarms. In some plants, these bays may contain any combination of one or more of the following: multiple rectifiers
(ferroresonant rectifiers 200 A and larger are often a bay unto themselves), the
PDSC, the controller, the power monitor (if separate from the plant controller), primary distribution fuses and/or breakers, converter plants, and residual ring plants.
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• SECONDARY DISTRIBUTION EQUIPMENT — is fed from the PBDs.
Secondary distribution includes Power Distribution Fuse Boards (PDFBs) for switches (they are known by many other switch-specific manufacturer names, such as LPDU, PD, PDF, PFD, GPDF, etc.), Battery Distribution Fuse and Circuit
Breaker Boards (BDFBs and BDCBBs), Area Bus Centers (ABC), and protective equipment. The PBDs and secondary distribution equipment may be combined in smaller power plants.
• CONTROL VOLTAGE — is the voltage used to operate alarm relays and control circuits in the power plant. The primary voltage of the plant should be the control voltage. This power is often provided off a small fuse panel called the
Alarm Battery Supply (ABS).
• CONVENTIONAL CONTROL and/or POWER SYSTEM MONITOR
CONTROLLER (PSMC) — there are two types of DC battery plant controllers used in CenturyLink: a conventional rectifier controller, and a combined rectifier controller / power monitor. When the power monitor is part of the controller, it makes reading power information via the monitor much simpler (there may also be stand-alone power monitors coupled with conventional controllers in some sites/plants). The Conventional Controller provides the interface between the rectifiers and the plant for "on and off" control under normal and adverse conditions. Both the Conventional Controller and a PSMC may provide for rectifier and plant alarms, and contain the visual readout devices for operation of the plant. They provide the means to assess the status of the elements of the power plant (with indications provided locally and remotely) that will permit determination of the impact of the alarm. All DC plants should only have a single main controller for all the rectifiers connected to that plant (sub-controllers that talk to the main controller are permissible), and no rectifier should be hooked up to DC plant busses without being connected to a controller, except in a temporary emergency. Monitors for use in larger sites shall be capable of monitoring plant alarms and any other alarms connected to them. Power monitors also measure analog values, such as voltages, currents, and temperatures. All power monitors shall have local port (serial or IP) access, and preferably be capable of dialup and emulation of a dumb terminal (i.e. VT100).
DC Grounding (and grounded) connections for electronic equipment locations shall be of the two-hole crimp (preferred), exothermic weld, or amphenol type (single-hole lugs are allowed for chassis grounds and for grounds where manufacturer specifications call for wire smaller than 14 AWG). Mechanical connectors or connectors that depend solely on solder are not acceptable.
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All DC power connections for both supply and return shall use crimp type copper connections and grade 5 steel nuts and bolts. Connectors for direct battery connections are defined herein. Aluminum connectors shall not be used. Power connectors will be configured as follows:
• Within the supplier's equipment, power connections will be configured to meet the supplier's requirements.
• Between the supplier's equipment in the bay and the top of the bay, connections can be one-hole or two-hole crimp, depending on equipment design.
• All connections to a battery return bus bar must be a two-hole crimp only.
Exceptions to the “two-hole” requirement are allowed for battery return bus bar rated at 50 Amperes or less.
Details for ground conductors can be found in CenturyLink ™ Technical Publication
77355, "Grounding - Central Office and Remote Equipment Environment".
RHW, RHH or XHHW Class I stranding are the preferred DC power and grounding cable types (for wire sizes smaller than 14 AWG, TFFN is allowed as long as it is protected at all tie points and points of impingement). This requirement does not apply to equipment in the CLEC area nor power runs to the CLECs, and is for new builds, and not augments or changes.
All power equipment (including rectifiers, batteries, ring plants, fuse panels, etc.) to be used in remote equipment enclosures (e.g., CEVs, huts, Customer Premises sites, RT cabinets) shall be fully front accessible where rear access will be needed and the equipment does not have a rear aisle or rear access.
It is preferred that the shunt for power plants rated at 800 Amperes or larger be in the battery return (grounded) side of the charge/discharge bus bar. For bus bar type and distributed type power plants (those without a remote chandelier), the shunt can be in the hot distribution and/or battery bus bar(s) located in the power board(s).
Low voltage disconnect devices are normally only permitted in series with the battery strings, not in series with the load (see figures 2-1 and 2-2) except for DSL loadshedding (when it is only allowed in series with the DSL loads). It is preferred that
LVDs not be used at all for DSL (unless DSL load shedding cannot be accomplished by the DSL equipment itself). LVDs are required (usually built into the battery charge controller) for solar stand-alone sites.
Broadband load shedding times typically vary from 5-30 minutes for FTTP and for
POTS/DSL combo cards not carrying video, and can be up to 90-120 minutes for video services from DSL cabinets not at the customer’s premises.
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2.3 Charging Equipment (Rectifiers) and Their Controller
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For proper plant operation, charging/rectification equipment shall have the following features or capabilities, whether they are required at the time of installation or not:
• HIGH VOLTAGE SHUTDOWN — for ferroresonant rectifiers will occur when high voltage on the DC output trips the high voltage alarm and causes rectifier shutdown. The high voltage shutdown setting shall be adjustable. Switch mode rectifiers’ HVSD is controlled by the plant controller.
• REMOTE RESTART — allows a rectifier to be turned on from a remote location after high voltage shutdown (usually be a ground signal on the R lead of the TR pair).
• REMOTE STOP — permits rectifier shutdown. Remote stop may be used during transfer from commercial to standby AC power or vice-versa or for energy management. This is usually accomplished by a ground signal to the T
(terminate) lead of the TR pair.
• CURRENT LIMITING — protects the rectifiers/charging equipment when operating in an overload condition. The current limiting circuit is normally designed so maximum output current will not exceed 120 percent of rating. The current limiting shall generally be set between 100 and 110% (alarm threshold levels for rectifier overcurrent are provided in Table 13-18).
• CURRENT WALK IN — controls the charging current from a gradual increase to full output. This feature limits the surge of AC power required after AC power restoration and allows the control circuits to stabilize. It typically takes at least 8 seconds for a rectifier to go from 0 to full load Amperes.
• LOCAL OR REMOTE SENSING — refers to the point where the output voltage is sensed for the feedback circuits. Local sensing (sometimes called “internal sense”) causes the rectifier to regulate the voltage at its output terminals. Remote sensing (sometimes called “external sense”) carries the regulation point to the battery terminals or some other selected point. Remote sensing is the only type that is allowed in plants with MTBs. Under no circumstances will local and remote sensing be mixed in the same power plant.
• AUTOTRANSFORMER — provides voltage matching of the AC supply, maintaining the nominal design voltage to the main transformers.
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• SEQUENCE CONTROL — provides the ability to turn rectifiers on sequentially, so that when AC is restored the load imposed upon the Standby engine or AC transformers by the rectifiers is sequential rather than block. Sequence control may be provided in rare cases from the power plant controller where it is necessary due to building engine load issues or rectifier component failure issues
(see Chapter 8, Paragraph 8.5.)
• PARALLEL CONTROL — is when all rectifiers are connected to the output DC bus at all load levels. The capability of each rectifier to monitor battery voltage individually and supply current on demand is called parallel control of charging units.
• TEMPERATURE COMPENSATION — Rectifiers to be used with Valve-
Regulated Lead-Acid (VRLA) batteries shall have slope temperature compensation charging features utilizing temperature sensors located at the batteries. The compensation shall be capable of lowering the voltage of the rectifiers to within one Volt or less of open-circuit voltage at 55° C (131° F).
• VOLTAGE ADJUSTMENT — Rectifiers to be used with VRLA batteries shall be voltage adjustable, both locally and remotely (e.g., sense leads).
• ALARMS and ALARM SETTINGS — shall be in accordance with Chapter 13 of this publication.
For proper plant operation, rectifiers/charging equipment may have the following additional features depending on the system size and equipment served:
• PROPORTIONAL LOAD SHARING — can be connected with other rectifiers and set to carry the load in proportion to the rating.
• ENERGY MANAGEMENT — automatically places rectifiers above and beyond those needed to meet the load into hot standby. This allows the remaining rectifiers to save overall plant kW-hrs by having those rectifiers operate closer to full load (where they are more efficient at converting AC to DC).
• PHASE SHIFTING — provides the ability for the AC input to be shifted to minimize the power factor in the AC input line (also known as power factor correction or PFC).
For single-phase switchmode rectifiers (including those that masquerade as 3-phase rectifiers by having 3 single-phase rectifiers in a common chassis), the AC current total harmonic distortion (THD) reflected back toward the source must be limited to 15 percent at full load. The third, fifth, and seventh harmonics must be 12 percent or less.
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For true 3 phase SMRs, the AC current THD reflected back toward the source must be limited to 35% at full load. The 3 rd , 5 th and 7 th harmonics must be 20% or less.
On power plants that use the controller to regulate float voltage, if the controller fails, the rectifiers shall default to 2.17 to 2.23 Volts per cell for long-duration flooded batteries and low-gravity VRLA batteries, and 2.25 to 2.27 Volts per cell for typical
VRLA batteries.
At startup, the total peak inrush current must not exceed ten times the steady state current requirement.
The power factor must be no less than 0.8 lagging or leading at loads of 10% or greater.
The acoustic noise shall be a maximum of 65 decibels audible (65 dBa), measured from a distance of two feet in any direction.
The DC ripple noise coming from the rectifiers shall be less than 35-decibel reference noise C-Message (35 dBrnC) and less than 300 mV peak-peak and 100 mV rms.
Power equipment for use in hardened equipment locations shall be capable of reliable operation at operating temperatures between -40 degrees and +65° C (149° F).
Any new rectifier should be capable of providing 60 V (for a nominal -48 V plant) or 30
V (for a nominal 24 V plant)
Each rectifier larger than 65 Amps should have its own dedicated AC connection (and it is recommended for even smaller rectifier sizes in COs, radio sites, and fiber regen huts). Where this is not the case in COs, radio sites and fiber regen huts, the “spare” rectifier becomes the sum of the rectifier output currents that would be lost if a single
AC branch circuit were lost (typically due to a tripped breaker). In customer premises and outdoor cabinet installations the shelf is often configured for two feeds, one for the even numbered rectifiers and the other feed for odd numbered rectifiers. One AC circuit cannot be used to power an entire RT or Prem rectifier shelf (unless the total shelf output capacity is less than 21 Amps nominal).
AC connections must be run in conduit or other raceway. Prems, where AC is provided by the customer, are exempted. Hard wiring is preferred, but locking-type plugs are allowed. If a standard three-prong plug is used, a plug with a ground screw (or similar to prevent the plug from being pulled out), should be used whenever possible. If this is not possible, the Customer must sign a waiver absolving CenturyLink ™ of liability in case of power plant outages (except for wall-mounted power supplies and equipment or equipment plugged into a rack-mount PDU in the same bay).
Green wire grounding (ACEG or “safety ground”) must be run with each AC rectifier feed for individually fed rectifiers. For multiple rectifiers fed from one source, each AC feed shall have its own ACEG to the shelf or AC feed at the top of the power board. All
ACEG must be run in accordance with the NEC ® .
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Bus bar type power plants powering a switch in a traditional isolated-integrated ground plane office must use a remote ground window (even if it’s only a few feet away), per
Tech Pub 77355.
Collocators may install rectifiers in their space (fed from CenturyLink-provided essential, non-essential, or uninterruptible AC feeds) with the permission of
CenturyLink. However, these rectifiers may not have batteries, flywheels, or fuel cells connected to their output bus as a backup DC source (unless it is an adjacent collocation). Customer-provided rectifiers must meet NEBS ™ Level 1 (see Section 1.6) for NEBS ™ spaces. For non-NEBS ™ spaces, the rectifiers must be Listed. The rectifiers used must meet the maximum reflected THD specifications cited previously in this section.
2.4 Engineering Guidelines
When sizing power plants, the following criteria shall be used:
• List 1 drain is used to size rectifiers and batteries, and cable voltage drop (see
Section 9.2 for the details on voltage drop sizing rules) in some cases (size batteries at the List 1 drain + 10% to account for the average increase in current of constant power loads during a discharge, and cable voltage drop in some cases is done at 125% of the List 1 drain to account for the peak current at the lowest possible voltage of a constant power load). List 1 is the average busy-hour current at normal operating voltage. While manufacturers may provide NEBS ™
List 1 drains, CenturyLink ™ refines them via lab/field evaluation and experience, because List 1 drains can vary widely based on take rates, percent fill, loop lengths, usage, etc. POTS List 1 drains are at 6 ccs at 52 V for nominal -48 V equipment. For non-POTS equipment, the equipment usage and fill rates used to determine a L-1 drain are specified by CenturyLink ™ consultation with the manufacturer. For example, an ONU with 16 broadband ports might be considered average with a 50% take rate (8 ports connected), 30% time usage of the connected ports, and 25% average broadband capacity use of the connected ports. If no other information is available, the initial size of a new DC plant may be calculated based on the sum of the individual List 1 drains for each equipment element, plus anticipated loads to cover forecasted growth. For installed operational networks, the annual busy-hour, busy-day current can be used as a proxy for the total installed equipment List 1 drain (since for sites with thousands of pieces of equipment, it is too burdensome to compile the total true
List 1 drain of all of the existing equipment). Future expected List 1 loads should be added to this proxy in order to size batteries and rectifiers for growth.
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• List 2 drain (or a proxy for it when unknown) is used for sizing circuit breakers and fuses; and is the peak current drawn at full capacity and bandwidth usage under worst operating conditions (typically lowest operating voltage, with startup currents for capacitor charging and locked rotor fans), as provided by the manufacturer. Telephony List 2 drains are measured at 36 ccs (or 100% usage at worst-case loop lengths). The minimum operating voltage is determined by the highest of the following values: the minimum operating voltage of the equipment given by the equipment manufacturer, or -42.64 V (for nominal -48 V equipment) or 21.32 V (for nominal 24 VDC equipment).
• List 3 drain is used for sizing converter plants. The peak current that is required by equipment at a regulated operating voltage should be used. For loads with no variability, the average busy-hour current at normal operating voltage should be used.
When a battery plant is initially installed, the meter and bus bar should be provided based on the projected power requirements for the life of the plant. Base rectifiers and batteries should be provided based on the projected end of engineering interval connected average busy-hour current drains (List 1).
One more rectifier should be provided than the number required for the "average busyseason busy hour drain" needed at the end of the engineering interval (n+1) for base rectifier requirements. The spare rectifier must be the largest rectifier in the plant. (In
COs, radio sites, or fiber regen sites, for non-individually fed rectifiers, the rectifier capacity of all the rectifiers that could be lost when a single AC breaker trips shall be used as the “largest rectifier”.) In remote locations carrying aggregate traffic of more than 500
Mbps, a minimum of 3 rectifiers and n+2 redundancy should be considered.
Size the rectifier plant such that it will carry the office busy-hour load with a minimum excess float voltage current capacity of 20 percent to recharge the batteries (1.20 recharge factor). For sites with float voltages of 53.8 or higher (or 26.9 for 24 V plants) this factor should be 25% due to the higher float voltage of most VRLA batteries. For NSD sites, the factor is 35% due to the high capacity traffic nature of these sites, the need to recover from an overdishcarge, and potentially long travel distances to get to the site to replace a rectifier. The capacity of the working spare rectifier is included as part of the recharge capacity. NSD sites shall have a minimum of 3 rectifiers (except at Customer Premises end-user sites where a minimum of two is OK) regardless of the preceding calculations.
The minimum recharge factors will charge 4 hours of battery backup that has been nearly fully discharged back up to better than 90 percent of full capacity in less than 24 hours.
For small power plants in remote terminal applications serving 96 or fewer POTS-only customers, rectifier redundancy is not required.
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Follow these general engineering guidelines:
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• Main conductors and feeders in the plant should usually be sized for the ultimate capacity of the plant. They should also be sized for a maximum temperature of
46° C (115° F). (See Chapter 9 for more information on distribution cable sizing.)
• Rectifier and battery capacity should be added as the load grows.
• Charge/discharge or supplementary bays should be added only as needed. The input cabling for these bays should be sized for the projected ultimate capacity
(typically the bus bar ampacity rating of the bay).
• Distribution equipment (fuses, or breakers) should be added only as needed.
• For power plants with rectifier sizes exceeding 65 A and VRLA batteries, the largest rectifier should be equal to or less than the total power plant load and recharge requirements. If not, turn off excess rectifiers (leaving 1 spare on). This will help to avoid extreme thermal runaway.
• For energy saving purposes, if total rectifier capacity exceeds the load plus the spare and recharge capacity, then all excess rectifiers should be turned off (either manually, with semiannual rotation into service; or by an automatic energy management algorithm from the plant controller). These rectifiers should be turned back on when the load and recharge capacity requires it. If the rectifiers are old, and/or at risk of capacitor dry out if turned off, don’t turn those off.
Power cable racking in the power room shall be located in accordance with
CenturyLink ™ Tech Pub 77351.
All rectifier cables and any battery cables not protected by a breaker shall be considered as unprotected (un-fused) leads. The charge leads shall be sized as follows for the rectifiers’ sizes listed:
• The voltage loop drop for the charge leads shall never exceed two Volts for the full loop.
• Leads to the charge bus for stand-alone 200-Ampere rectifiers shall be one 350 kcmil per battery and return.
• Leads to the charge bus for stand-alone 400-Ampere rectifiers shall be two 350 kcmil per battery and return.
• For smaller rectifier sizes (or the rare 800 A rectifier), follow manufacturer recommendations for the leads to the charge bus.
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• For rectification bays/shelves, follow the manufacturer recommendation for the leads to the charge bus, ensuring that the ampacity of the cables used exceeds
120% of the rectifier shelf/bay capacity (this may be reduced to the maximum current limit possible for rectifiers whose maximum current limit at any voltage is less than 120% of the rating), and that the voltage drop does not exceed two
Volts for the loop. Note that cable ampacity is determined from NEC ® Table
310.15B16 as modified by Articles 110.14C and 240.4D. Derating of ampacity due to cable rack pileup in larger sites (which is ultimately related to temperature) below these values is not necessary due to maximum cable rack temperature limitations found in Technical Publication 77350, and due to the oversizing of most cable because of voltage drop calculations.
• Rectifier output leads over 125 feet one-way shall be sized using the manufacturers’ recommendations (where available), ensuring that the voltage drop does not exceed two Volts for the loop.
2.4.1 Example of Proper Calculation and Usage of List 1 and List 2 Drains
Equipment manufacturers often give power drain information in many formats, including, Watts, Amps, recommended fuse size; etc. It is often necessary to speak with the equipment manufacturer to clarify true List 1 and List 2 drains. To help understand List 1 and List 2 calculations for sizing batteries, rectifiers, fusing, and wires, an example might be helpful. The following assumptions apply for this example:
• the relay rack / bay to be added will be equipped with 3 shelves of EoCu
(ethernet over copper) equipment o the shelves are A/B fed, each with 14 slots
of those 14 slots, 7 are normally fed from the A side, and 7 from the B, but during a failure of one fuse, the shelf is diode ORed in the backplane so that all 14 slots can be fed from either the A bus or the B bus o the cards that can be placed in the shelf are either short-reach, mid-range, or long-loop cards
the typical draw of a short-reach card is 24 W, and its capacitor charging current is limited to 143 mA
the typical draw of a mid-range card is 31 W, and its capacitor charging current peaks at 184 mA
the typical draw of a long-loop card is 45 W, and its maximum capacitor charging current is 265 mA
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the distances of the EoCu spans vary by site, so mid-range cards are assumed to be average in this example for calculation of the List 1 drain, and long-loop cards are used to calculate List 2 drain
• for both List 1 and List 2 cases, it is decided for this particular example that the shelves will be fully-populated for planning purposes
• the relay rack / bay also has a variable speed fan shelf, fed only from the A side of the miscellaneous fuse panel at the top of the bay o the draw of the fan shelf at full speed is 144 W
full speed will be used for the List 2 calculation in this example o the draw of the fan shelf at mid-speed is 98 W
mid-speed will be used for the List 1 calculation in this example o the locked rotor current of the fans is 2.5 times the full-speed fan current o the momentary draw of the starter capacitors in the fan shelf is currentlimited (by resistors in the fan shelf) to no greater than 500 mA.
• the nearest BDFB is 45 feet away via cable rack, and will take fuse sizes up to
100 Amps
• the PBD is 130 feet away via cable rack path routing
• All wire, lugs, and termination pads on the PBD, BDFB, and miscellaneous fuse panel are rated for at least 75° C
• 8 strings of flooded 1680 Ah batteries in the DC plant, floating at -52.80 V o the site is backed up by a permanent engine-alternator
the 4-hr rate of each string of batteries to 1.86 V/cell (see Table 3-1) is
280 A
• per Section 3.8, this value is de-rated by 10% to account for aging:
280 𝐴𝐴 × 90% = 252 𝐴𝐴
• existing -48 VDC plant busy-hour load during the last year (as recorded by the power monitor) was 1,713 A
• The plant presently has twelve 200 A rectifiers
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The List 1 drain of the A side of the bay is:
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The List 1 drain of the B side of the bay is:
The total List 1 drain of the bay is:
Before calculating the List 2 drain of the bay, it is necessary to calculate the lockedrotor fan shelf current:
The List 2 drain of the bay is:
Now that List 1 and List 2 drains have been determined, the impact on rectifier and battery sizing can be determined.
As noted earlier in Section 2.4, the existing busy-hour load can be used as a proxy for the existing List 1 drain of the equipment in the office. To that can be added the List 1 for the new equipment:
This number must then be compared to the n-1 rectifier capacity, and the recharge capacity. The n-1 rectifier capacity is:
Per Section 2.4, because the float voltage of the plant is less than 53.8 V, the recharge factor is 120%:
This number must be less than total rectifier capacity (and it is):
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What these calculations mean is that the existing plant has enough capacity to handle the new bay. However, typically, for growth purposes, because it sometimes takes a little bit of time to engineer additional rectifier capacity, the Engineer wants to be informed when the load has reached 80-95% of the rectifier n-1 or recharge capacity.
Running these calculations yields, respectively:
Based on the second of these calculations, the ease of adding rectifiers to the existing plant, and what the Engineer knows about future growth, the Power Planning
Engineer may or may not want to start a plan to add more rectifiers?
As noted in Section 2.4, 110% of the projected List 1 load is used for battery sizing to account for the increase in current during battery discharge:
The total age-derated battery plant capacity is:
8 𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 × 252 𝐴𝐴 𝑝𝑝𝑝𝑝𝑠𝑠 𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 = 2,016 𝐴𝐴
Running a capacity calculation for what battery plant capacity will be yields:
While there is enough battery capacity to add the new bay without embargoing the site for equipment additions, the Power Planning Engineer will probably want to start a job to add batteries soon.
1,917 𝐴𝐴
2,016 𝐴𝐴 = 95%
The miscellaneous fuse panel at the top of the new bay needs to be fed with fuses that are at least 125% of the List 2 drain (see Section 9.5).
Rounding up to the next common fuse size means that a minimum 90 A fuse is needed at the PBD or BDFB to protect both the A and the B feeds to the miscellaneous fuse panel at the top of the bay, and the miscellaneous fuse panel needs to be rated to carry that current as well (common ampacities for miscellaneous fuse panels near this number are 60 and 100 Amps, so a fuse panel capable of carrying 100 A with its buswork would be needed).
Voltage drop sizing from the PBD or BDFB, done per the rules of Section 9.2 would be based on 125% of the List 1 drain.
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For the A feed, that value is:
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For the B feed, that value is:
Because both the BDFB and the PBD are capable of accepting a 90 A fuse, it may be useful to run voltage drop calculations for both scenarios:
Using the rules of Section 9.2 yields the following voltage drop wire-sizing calculation from the BDFB for the A side:
And for the B side:
Per Table 9-4, either calculation would require the use of a minimum of 4 AWG; however, per that same table, at the 75 °C rating, that cable size only has an ampacity of 85 A, which does not equal or exceed the 90 A fuse so; therefore, 4 runs
(A feed, A return, B feed, and B return) of #2 AWG (ampacity of 115 Amps) must be used in order to feed the miscellaneous fuse panel from the BDFB.
Running the same calculations for a feeder set from the PBD yields:
As previously, voltage drop calculations require a minimum of #4; however, the cable must be upsized to #2. Because four 45 ft runs of #2 from the BDFB are going to be much less expensive than four 130 foot runs of #2 from the PBD, the Engineer should choose to feed this bay’s miscellaneous fuse panel from the BDFB.
2.5 Power Board Panel and Fuse Numbering for New Power Plants
This requirement is for new power plant panels and fuse numbering to accommodate newer system requirements. Existing power plants will continue with the existing numbering system, and are not affected by this requirement.
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New power plant distribution bays will have panel labeling starting with Panel 01
(PNL-01) from the bottom in each bay to Panel XX (PNL-XX) at the top of the bay. Each panel’s fuse positions will start with Fuse 01 (FS-01) to Fuse XX (FS-XX), which would be the last fuse number of that panel. This will allow fuse panels to be removed or added and not affect the fuse numbering in the bay. If multiple panels exist on a given level numbering will start in the lower left corner of the bay with PNL-01 proceed left to right on that level with PNL-02 then proceed up and left to right for additional panels in the bay. Fuses will be labeled left to right or top to bottom depending on the panel’s orientation. Fuse positions will be assigned in the power boards from the bottom up.
To satisfy NMA ® requirements in some power monitors, a unique 7-digit number will be created as follows:
• 1st digit “ P ” for power plant bay
• 2nd and 3rd digits will be the last 2 digits of the bay number (P0101.
03 )
• 4th and 5th digit will be the panel number (PNL04 )
• 6th and 7th digit will be the fuse number on that panel (FS08 )
• For the example shown above, the NMA ® identifier would be P030408.
— When the installer is ready to test fuse/breaker capacity alarms for the new NMA ® numbering of the Power Board panel and fuse, mention to the technicians in the NMA ® database group that these distribution numbers are not template generated and need to be manually databased.
In distributed power bays where rectifiers and distribution exist in the same bay, rectifiers are labeled as G-01 to G-XX in that bay from the bottom to top, left to right, as required, and continue with the next consecutive rectifier number in additional bays.
The distribution panels will start with Panel 01 (PNL-01) wherever the first distribution panel starts in that bay and is then labeled from bottom to top. In additional bays, the distribution panels will always start with Panel 01 (PNL-01) where the rectifiers will continue with the next consecutive rectifier number.
Specific examples are shown in the CenturyLink ™ configuration (Q&A) help files for a particular power plant. This aid is to help and assist planners, engineers, installers, and suppliers.
2.6 Conventional Controller
The traditional power plant controller shall be capable of basic alarm and control functions as described below. In some COs, the alarms will be connected to an
“intelligent” power monitor/controller (PSMC) as described in Chapter 8.
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All provided alarms must be capable of being monitored remotely. The connecting point for these contacts will be easily accessible. All analog monitoring points (current shunts or Volt meters) within DC plants larger than 100 A of capacity will be equipped with terminal strip access for attaching remote monitoring devices. The connecting point for analog monitoring points will be located near the alarm connecting points and be easily accessible. Binary alarm thresholds from analog points shall be settable. The following alarm indications shall be provided:
• Power Minor Alarms (generic summation power minor shall also be available)
— Rectifier failure - single rectifier failure
• Power Major Alarms (generic summation power major shall also be available)
— Discharge fuse
— High Voltage
— Low Voltage and/or Battery on Discharge (BOD)
— Voltmeter and voltage regulator fuse
— Charge fuse
— Rectifier failure - multiple rectifier failure
• Power Critical Alarms
— Very low Voltage (may not be remoted depending on legacy company)
— High Voltage ShutDown (HVSD)
When the power plant controller (each DC plant should only have 1 master rectifier controller – there may be sub-controllers for differing rectifier types) and the power monitor are separate entities, the power plant controller major and minor alarms should be paralleled with the PSMC major and minor on the e-telemetry device or switch in case the PSMC fails.
Control functions of a traditional controller will be limited to high-voltage shutdown and restart capabilities, as defined herein; and rectifier sequencing.
Plant controllers for 50 Ampere plants and larger must have digital voltage and current meters (this may be a combined meter). Power plants with a capacity of less than 50
Amperes are not required to have a meter, but shall have test jacks so that the plant voltage and current can be measured with a meter.
Rectifiers whose outputs are controlled by the power plant's controller must default to the rectifier's settings if the controller fails.
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Chapter 3
Batteries and Battery Stands
Chapter and Section
3.
CONTENTS
Page
Batteries ....................................................................................................................... 3-1
3.1 Overview ......................................................................................................... 3-1
3.2 General Description ....................................................................................... 3-1
3.3 Battery Discharge Characteristics ................................................................ 3-1
3.4 Battery Recharge Characteristics ................................................................. 3-3
3.4.1 Ventilation of Battery Areas ....................................................... 3-4
3.5 Battery Configurations .................................................................................. 3-5
3.6 Battery Types .................................................................................................. 3-6
3.7 Selection ......................................................................................................... 3-10
3.8 Sizing .............................................................................................................. 3-11
3.9 Battery Stands and Connections ................................................................ 3-12
3.9.1
3.9.2
Metal Stands, Trays, and Compartments/Boxes .................. 3-12
Round Cell Stands...................................................................... 3-13
3.9.3 Battery and Stand Installation and Intercell Connections.... 3-14
3.10 Battery Disconnects ..................................................................................... 3-18
Tables
3-1 Typical Battery Disconnect Sizes for Long-Duration Flooded Lead-Acid ....... 3-19
3-2 Typical Battery Disconnect Sizes for Ni-Cd Batteries .......................................... 3-19
3-3 Typical Battery Disconnect Sizes for Long-Duration VRLAs ............................. 3-20
Figures
3-1 Typical Arrangement of Cables for a Flooded Battery Stand ............................. 3-17
3-2 Minimum Dimensions for a Bus Bar Above Flooded Battery Stands ............... 3-17
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3. Batteries and Battery Stands
3.1 Overview
This unit covers requirements for batteries and battery stands used within telecommunications facilities.
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3.2 General Description
During short term commercial alternating current (AC) disturbances, telecommunications equipment is operated on the direct current (DC) reserve power typically supplied by batteries. The reserve battery power required for telecommunications sites with lifeline service are 4, 8, or more hours (the 4 and 8 hour backup requirements are based on history, FCC Best Practices, and various state regulatory rules), as described herein (non-lifeline services, such as DSL, have no minimum battery backup standards unless they are on a combo card with POTS services). During normal AC power operation, batteries are maintained in a fully charged or float condition.
Some computer systems, such as Operational Support Systems and data processing centers, require an Uninterruptible Power System (UPS) to furnish continuous AC power to their loads. The UPS consists of chargers and inverters with an associated battery reserve. Reserve time for UPS systems is typically 15-45 minutes, although it can be more or less. This allows uninterrupted operation through brief power disturbances or, if necessary, provides the time for a smooth shutdown or transfer to a standby AC source. A UPS system with less than 4 hours of battery backup shall
NEVER be used as backup for telecommunications Network loads critical to ensuring
Network lifeline operations.
All materials used in battery cases shall have a minimum limiting oxygen index (LOI) of
28% (per ASTM standard D2863), and meet the UL ® 94 V0 burn requirement. Battery cases shall have sufficient strength to withstand normal handling and internal pressure generated by positive plate growth (within their design lifetime) and/or discharging and recharging.
3.3 Battery Discharge Characteristics
Battery strings designed for use with standard DC Central Office plants provide at least
4 hours of reserve time. On discharge, as a lead-acid battery initially supplies the load current, the voltage will rapidly drop, then levels out, (turnaround voltage) before rising to a slightly higher voltage (plateau voltage) before beginning to fall again. This phenomenon is referred to by the term “coup de fouet” (crack of the whip).
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During the remaining discharge, the voltage falls slowly until the "knee" of the curve.
At this point, further discharge results in rapid voltage drop caused by electrochemical depletion of the cell. Plots of "initial voltage" versus discharge Amperes are available from battery suppliers as either separate curves or part of the normal discharge curves.
A plant and its loads are designed to operate to minimum lead-acid discharge voltages of 1.94 - 1.63 Volts per cell (also known as end or cut-off voltages). Voltage below 1.75 on long duration discharges can indicate reversed (non-recoverable) cells. The MVPC
(minimum Volts per cell) for chemistries besides lead-acid is determined from the end voltage of the equipment, (typically no higher than -42.64 for nominal 48 V equipment) plus the voltage drops defined in Chapter 9, divided by the number of cells per string.
The coup de fouet and the voltage at the knee of the discharge curve depend on the discharge current, cell type, float voltage, and amount of time since the last discharge; and they are generally lower at higher discharge currents relative to battery capacity.
A fully charged (1.215 specific gravity) lead-acid wet/flooded cell has an open circuit voltage of about 2.06 Volts after a day or two off of charge (this will decrease with time off charge). The "calculated" open circuit voltage of a lead-acid battery can be found by adding 0.85 to the specific gravity of the electrolyte of that battery. The minimum recommended float voltage could be found by adding 0.95 to the specific gravity (the bare minimum voltage needed to keep the cell charged is a little less than this).
The highest voltage reached during a discharge after the lowest coup de fouet voltage is sometimes referred to as the plateau voltage. The lowest coup de fouet voltage is sometimes called the turnaround voltage
.
Batteries shall be floated and alarmed at the levels prescribed in Chapter 13. Exceptions to this include flooded batteries that are installed in some old WECO 100 or 300 series plants with their original controller. They should generally be floated at 2.17 Volts per cell due to the inability to change some alarm and HVSD thresholds in these plants.
The first and last cells of a flooded string should not be adjacent on the same shelf.
They should be either on opposite ends of the shelf or on separate shelves. Cell 1, the positive end of the string, should be on the lower tier on two-tier stands where a string uses both tiers. Exceptions are allowed for small VRLA batteries rated at 250 Ah or less.
Exceptions are also allowed for flooded batteries where placing the first and last cells next to each other is more convenient due to existing busbar and/or cable-racking arrangements. In those cases, the terminals and term plates shall be protected with insulation, and an effort should be made to separate them by at least 12 inches in order to avoid accidental shorting from dropped tools or other metal objects.
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Follow the manufacturers’ recommendations for installation of all batteries. Each cell in the battery string shall be numbered, unless it is a monobloc (multicell battery) with an opaque jar. The numbers should be placed on the battery stand under the corresponding cell where possible, or on the battery if that is not possible.
3.4 Battery Recharge Characteristics
A float voltage of 2.20 Volts per cell, for flooded type lead-calcium, nominal 1.215 s.g. batteries, available from rectifiers in typical DC plants, not only maintains the batteries at full charge, but also recharges them after discharge. Whenever the DC plant and the equipment being served will accept a power plant voltage by floating the batteries at
2.20 Volts/cell (as opposed to the older 2.17 Volts/cell typically used for lead-antimony batteries), the higher float voltage should be used. This higher float voltage will result in reduced maintenance and longer battery life.
If an office loses commercial power and is required to use battery power for several hours, the batteries must be recharged when commercial power returns. If the rectifiers can deliver much more current than the load requires, the batteries will recharge quickly. However, there is a danger in having too many rectifiers for certain battery types. If the batteries recharge very quickly, they are receiving a lot of current. Because of the internal resistance of the battery, heat is generated when current passes through the battery, on either discharge or recharge. If too much current passes through the batteries, some older VRLA batteries are not able to dissipate all of the heat, and may go into thermal runaway. Also, Li-based batteries have a charge current limiting circuit that may disconnect the batteries if too much charge current is flowing to them.
Therefore, it is unwise to oversize the rectifiers to recharge the batteries quickly. Use the n+1 and 120 or 125% rules described in Chapter 2 for proper rectifier sizing to the load, and recharge. As a general rule do not leave more than 200% of the load in rectifier capacity turned on (lockout/tagout excess rectifiers) unless it is necessary to meet the n+1 and 120 or 125% recharge rules. Recharge time will be lengthened when current limiting or temperature compensation is used with VRLA batteries. Although this slightly compromises reliability, safety concerns necessitate the use of these devices.
New flooded cells are given an initial boost charge at a relatively high voltage to help finish “formation” of the plates. This charge usually lasts several days (follow manufacturer recommendations), and care must be taken to prevent a buildup of
Hydrogen gas in the battery area. In addition, individual cells may sometimes become weak (with a depressed voltage and/or specific gravity) over time. Sometimes boost or equalize charging (equalize charging is very similar to boost charging) for the individual cells may bring these weak cells up to proper float voltage.
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Boost charging is also sometimes used on flooded cells to recharge the batteries quickly if they have recently experienced multiple deep drains and there is a fear that there are more commercial AC outages pending in the near future. Boost charging is commonly used in solar/cycling/photoVoltaic applications.
Valve-Regulated (VRLA) batteries are much more susceptible to thermal runaway at high voltages than are flooded cells. For this reason, all plants equipped with VRLA batteries going forward must employ temperature-compensated charging. Preferably, there will be one cell/monoblock monitored per string (typically the most negative cell/monoblock in the highest row of the string), with the highest temperature determining the float voltage compensation.
VRLA batteries are also sometimes contained in a relatively confined space, enabling the possible buildup of volatile concentrations of Hydrogen during thermal runaway.
For this reason, boost (including initial boost) and equalize charging of VRLA batteries is strongly discouraged (except in PV applications). These batteries can be placed in service and will finish plate formation and recharge over time (they also receive a better formation charge at the factory than a flooded cell). Safety takes precedence over having a fully-charged battery all of the time. If boost or equalize charging is done to
VRLA batteries, ensure that manufacturer’s recommendations are strictly followed, and the batteries are checked on frequently for abnormal heating or gassing.
Note that not all lead-acid batteries are designed with the same types of plates. UPS and engine start batteries typically have thinner plates (thus they can get current out quickly in a smaller footprint but won’t last as long), and VRLAs used in UPS or engine-start applications are typically of the AGM type (see Section 3.6). Cycling/solar or engine-start batteries may have antimony in the plates, or other special manufacturing methods to ensure at least 800 cycles to an 80% depth-of-discharge.
3.4.1 Ventilation of Battery Areas
All aqueous batteries (such as lead-acid and Ni-Cd) gas potentially explosive
Hydrogen; especially during thermal runaway, boost charging, or equalize charging.
Under normal float operating conditions, flooded cells will gas much more
Hydrogen than a VRLA battery (under normal operating conditions, the VRLA battery should be recombining much of the Hydrogen with Oxygen to replace the water). However, during the first year of service for VRLAs (especially for gel technology), the VRLA may gas the same amount as an equivalent flooded cell. In addition, under thermal runaway conditions VRLA batteries are capable of gassing incredible amounts of Hydrogen; and under extreme thermal runaway conditions; they may even gas potentially toxic Hydrogen Sulfide.
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Because of these potentially toxic and explosive gasses, it is very important to ensure that battery rooms/compartments/areas are adequately ventilated. Hydrogen buildup in battery rooms/areas or compartments should be limited to approximately 1% (the LEL — Lower Explosive Limit — of Hydrogen is 4%). This applies to battery rooms as well as battery compartments in cabinets.
As a minimum, CenturyLink ™ has adopted a minimum air change rate of 0.5 ach (air changes per hour), unless other calculations are done ensuring that Hydrogen concentrations do not exceed 1% under boost charge conditions (this is a Fire Code requirement). In the great majority of cases, 0.5 ach will ensure that Hydrogen concentrations do not exceed 1% (see IEEE 1635 / ASHRAE 21 for gassing and ventilation calculation methods to meet the Fire Codes). Note also that normal occupancy calculations require even greater than 0.5 ach for “occupied” rooms.
For Customer Premises cabinets, both the cabinet itself and the surrounding room should meet the air change and Hydrogen buildup guidelines.
Engineers typically do not prefer to design excessive air changes into the ventilation system, as this would compromise thermal efficiency of the HVAC, especially in hot or cold climates. In some cases, redundancy and/or DC-powering are designed into the ventilation system to ensure that there will always be minimal ventilation.
Some “confined space” applications (like CEVs) also require alarming or testing before entering for toxic and explosive gasses (as the Hydrogen vented by batteries).
The alarm levels are set by OSHA and are outside the scope of this document (more information on gas monitoring can be found in Telcordia ® GRs 26 and 27).
Note that Li-based batteries do not gas, and thus do not require ventilation
(although if they are used in “people space” there must be ventilation for personnel).
3.5 Battery Configurations
General descriptions of a battery plant, its configuration, sizing, etc. are in Chapter 2.
Cells with different recommended float voltages cannot be mixed. For example, most
VRLA and flooded cells can’t be placed in the same plant (although low-gravity VRLA strings may be paralleled with flooded cells if a CenturyLink ™ Power Maintenance
Engineer has reviewed it and a Letter of Deviation is signed [see Tech Pub 77350 for
Letters of Deviation]). Differing string sizes and battery manufacturers may be used in the same plant; however, this is discouraged for VRLA batteries. Cells of differing sizes and/or manufacturers shall not be used in the same battery string, unless the battery is no longer manufactured; in which case consult the manufacturer for replacement alternatives. If replacement alternatives do not exist, then replace the entire string.
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Battery rooms (or exterior doors to small buildings containing rechargeable batteries) must be equipped with the appropriate signage as required by the Fire and local Codes.
3.6 Battery Types
CenturyLink ™ uses several battery technologies in equipment locations. The characteristics and requirement of the battery types are not always interchangeable.
The CenturyLink ™ Engineers are responsible for the sizing of the battery reserve of a site .
The battery technologies used in CenturyLink ™ are:
• FLOODED LEAD ACID — flooded (also known as wet or vented) lead-acid batteries are the "traditional" batteries used in large telecommunications equipment locations. This group of batteries includes the pure lead, leadantimony, and lead-calcium battery types. Lead-antimony batteries are not to be used by CenturyLink ™ going forward except in engine-start and cycling
(solar/photoVoltaic) applications. If it is feasible to use flooded batteries, they should be used. Lead-calcium is the preferred battery type for long duration float applications. The manufacturer is required on new flooded battery strings to ship us a voltage-matched set (all cells within 0.03 V of each other on formation charge) manufactured within a month of each other.
In lead-antimony cells, antimony is added to the plates to add mechanical strength. As these batteries age, they develop higher and higher self-discharge rates, require higher trickle currents, and need greater maintenance because of higher water loss from gassing than other flooded cells. A 1680 Ampere-hour lead-antimony cell takes approximately 550-650 mA of float current when new, and 1100-1300 mA when approaching end-of-life. The Ampere-hour efficiency, calculated by dividing the Ampere-hours of discharge by the Ampere-hours required to restore the cell to full charge, is lower for these cells than for most other types. The average expected life on float at 77° F is 14-15 years, based on experience. (When these batteries start using an appreciable amount of water
[over half a gallon per month], they must be replaced immediately!).
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While new lead-antimony cells are no longer allowed in CenturyLink ™ for long duration standby applications, European lead-selenium (low-antimony; i.e. less than 2%) designs are a good compromise between between pure-lead or leadcalcium and lead-antimony (5-8% antimony content in the positive plate grids), and may be used. While float current and watering needs increase towards the end-of-life of a lead-selenium cell (they should last 18-20 years), the effect is not as severe as in a standard lead-antimony design, and the need to water the cells frequently towards the end of their useful lives can be mitigated by using flame-arresting vents equipped with catalysts that recombine some of the electrolysis-evolved hydrogen and oxygen back into water. All designs with antimony in the plates (whether lead-antimony or lead-selenium) selfdischarge faster than most other battery types, and thus their maximum storage interval without a freshening charge is typically no more than 3 months
(shorter in higher temperature environments).
The lead-calcium cell design results in lower self-discharge, lower trickle charge current and less maintenance than the lead-antimony design. However, the condition of the cell is more difficult to determine using specific gravity
(other than initial installation inspection, specific gravity readings are discouraged for pure-lead and lead-calcium cells) and voltage readings because of the lower gassing rate and; therefore, limited electrolyte gravity change.
In float operation, the cells take 60 to 300 milliamperes of float current for a
1680 Ampere-hour cell. Experience has shown an average life on float at 77° F of 18-20 years.
Lead-calcium and lead-selenium cells shall not be used in the same string due to differences in charge/discharge rates, and the possibility of electrolyte contamination from maintenance activities, etc.
The pure lead flooded cell is designed to minimize the physical deterioration associated with conventional designs. The float current range for these cells is similar to that for lead-calcium cells. The expected life on float of the second generation of these cells at 77° F is better than 40 years. The pure lead flooded cell most commonly found in the U.S. is also known as the “round” cell, or the
“Bell” cell (there may also be expensive European pure lead thick-plate rectangular designs known as Planté). (There are also pure lead and pure leadtin VRLA designs, and while they won’t last 40 years, they will last longer than other VRLA alloys in float service, and like pure lead flooded designs, they store very well, lasting 12-18 months without a freshening charge, as opposed to the typical 6 months for lead-calcium designs.) While the round cells last a long time, they were extremely expensive, so the demand was low and the manufacturer eventually stopped making them.
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• VALVE REGULATED — Valve-Regulated Lead-Acid (VRLA) batteries include both the starved electrolyte (absorbed glass mat or AGM), and immobilized electrolyte (gel) technologies. Starved electrolyte should be avoided whenever possible in CenturyLink ™ Local Network (LNS) Central Offices (with the exception of engine-starting applications), and when used in such applications should almost always be in a “centralized” power plant. A "characteristic problem" of valve regulated batteries is the potential for thermal runaway.
Suppliers of VRLA batteries will provide "safe operating environment" characteristics with VRLA batteries.
Most VRLA batteries typically require a higher float voltage than flooded lead acid batteries. Rectifier plants supporting valve-regulated batteries should be able to sustain a float voltage of up to 2.31 Volts per cell. VRLAs shall not be boost or equalize charged unless they have not been charged for at least 6 months or are in service in a PV application. In those cases, follow the suppliers’ recommendations for charge times and charge voltages.
For -48 Volt plants, twenty-four battery cells should be used for each string wherever possible. This also applies to +24 Volt plants, where twelve battery cells must be used for each string.
• NICKEL CADMIUM — Ni-Cd batteries used within CenturyLink ™ are generally based on a flooded technology. Because of their relatively small capacity, low cell voltage, and high cost, Ni-cd battery use is generally limited to standby engine-alternator start/control batteries or RT cabinet batteries in higher temperature environments (although some models can have a slight space advantage over some VRLA batteries and so may be used in certain cabinets in all climates where the extra capacity in the available battery compartment space is needed), or cycling/solar batteries in low temperature environments. Ni-Cd batteries are also excellent for areas (such as hurricaneprone areas) that might experience a deep discharge followed by days or weeks without power (they recover much better from overdischarge abuse conditions than lead-acid). Ni-Cd batteries used by CenturyLink ™ for longduration backup typically ship with a very low state of charge, which enables them to be stored for periods of 12-24 months without a freshening charge, but will cause a large current draw when they are first connected to a dc bus without a pre-charge. The long-duration Ni-Cd batteries used in
CenturyLink ™ are packaged in multi-cell blocks, but it takes 38 cells to make a nominal 48 V string, so there are odd block sizes. Lead-acid cells are also used as start or control batteries for engine-alternators in CenturyLink ™ Equipment, in traditional flooded, maintenance-free flooded, and VRLA designs.
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• NICKEL-METAL HYDRIDE (NMH) — Like Ni-Cd, NMH (or NiMH) is an alkaline (potassium hydroxide electrolyte, which means it must be neutralized with an acid instead of the typical baking soda basic solution used for lead-acid batteries) chemistry. Alkaline chemistries generally have a nominal voltage of
1.2 V/cell (as compared to nominal 2 V/cell for lead-acid chemistries and 3-4
V/cell for Lithium chemistries). The actual charging and open-circuit voltages for NiMH cells are very similar to those of Ni-Cd cells. Often, the individual cells are pre-packaged into a nominal 12, 24, or 48 V monobloc. Nickel-metal hydride cells have been deployed as a longer life alternative to lead-acid cells in some distributed power constant current charging RT applications, and are under consideration (along with Li-based batteries) for constant voltage applications where they can save space and weight. Temperature compensation must be employed when these batteries are used with traditional telecom constant float voltage rectifiers (although this can be accomplished through a BMS integrated into the battery itself).
• LITHIUM — The sealed nature of Li-based batteries eliminates traditional concerns of out-gassing. Construction of battery modules in integral 48 or 24 V monoblocs eliminates the series connection of modules to achieve the required plant potential.
Lithium-ion (Li-ion) has been popular for portable applications (cell telephones, camcorders, laptops, etc.), and is presently in the early stages of deployment for larger stationary applications incorporating both high rate and long duration discharge applications (note that like lead-acid cells there are internal differences between high-rate and long duration discharge cells). A
Li-ion cell consists of lithium ions imbedded in a carbon-graphite substrate
(positive plate) or a nickel-metal-oxide, or a polymer phosphate. The electrolyte is a liquid carbonate mixture, or a gelled polymer. The lithium ions are the charge carriers in the battery.
There is no gassing, no free electrolyte, and no hazardous materials with
Lithium batteries. Li-ion batteries are best-suited for indoor environments.
Most Li-ion batteries can be used in remote applications, but with reduced life in high-temperature environments. The shelf life of most Li batteries is 2 years plus, provided the parasitic loads of the built-in charge-control circuitry are put to sleep.
The drawback to Lithium is that it is an extremely reactive metal (it reacts in free air). This means that sealing the battery and controlling the charge current are very important. Controlling the charge current is done quite well with electronics imbedded in the battery.
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Due to the electronic charge current controls, the newness of the technology, and the clean-room manufacturing environment, Lithium-based batteries are more expensive initially than their lead-acid counterparts. However, where gassing, high-temperature environments, space, or weight are an issue, lithium batteries can pay for themselves in 6 years or less.
Lithium-ion based cells used in CenturyLink ™ up to this point have a charge voltage of between 3.4 and 4.1 V (depending on chemistry). However, charge voltages too close to the top end shorten battery life, while those closer to the bottom end reduce capacity. Open circuit voltage for these cells is 0.05 V below the charge voltage. Expected life for stationary Li-ion batteries is expected to be 15-20 years (regardless of environment), with a minimum of 10, and possibly a maximum of 25 or more years. The cells may be cylindrical (spiral-wound) or prismatic (rectangular), and typically packaged in series "blocks" to achieve higher individual module voltages. In some cases, these monoblocs may be packaged in rack-mountable metal-encased "shelves" that can mount in a relay rack.
• SUPER/ULTRA™ CAPACITORS — Electric double charge layer capacitors
(commonly known as super- or ultra™-capacitors) using carbon-based electrodes have made capacitances of thousands of Farads possible in small, packages. For very short duration discharges (less than a few minutes), they provide an economic alternative to batteries. Generally, due to their extremely low internal resistance, they must be coupled with a DC-DC converter or a charge current limiter to be used with existing DC plant rectifiers.
3.7 Selection
The selection of battery type and size for an installation depends on:
•
Initial busy hour load and estimated growth pattern with time
•
Added Power failure loads (such as AC-preferred inverters and switched DC lighting)
•
End voltage per cell
•
Office reserve requirements
•
Battery aging characteristics
•
Ultimate Power Plant size
•
Temperature
•
Environmental constraints
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For a new plant, the optimum battery stand and floor layout is achieved by using only one battery model. However, strings of different types and sizes may be mixed. The
CenturyLink ™ engineer will determine the type and manufacturer of the batteries to be used.
In RT cabinets, where the temperature of the battery compartment will regularly drop below 30 degrees F in the winter, battery heater pads should be installed where leadacid batteries are used. They normally operate when the temperature is below 40 degrees F, and normally do not operate when the temperature is above 50-60 degrees.
3.8 Sizing
At least 4 hours of battery reserve shall be provided for sites serving lifeline POTS with a permanent on-site auto-start, auto-transfer engine (this reserve can be reduced to an hour for traditional CATV sites with an engine). Sites served by a portable genset that serve lifeline POTS loads shall have at least 8 hours of battery reserve, unless they have a host, tandem, standalone, or long distance switch, in which case they shall be equipped with a permanent auto-start, auto-transfer engine, or contain at least 24 hours of battery backup.
Note that per section 2.4, battery sizing is calculated at 110% of the List 1 drain. In addition, the standard accepted end-of-life figure for most batteries is 80% capacity (this represents the point in the capacity vs life curve of a lead-acid battery, where capacity begins to fall off rapidly as time goes on). Because of the general dropoff in capacity as a battery ages (some battery types actually increase in capacity for the first few years of life, but some of these begin their life at less than 100% of rated capacity), and because in larger sites, the parallel battery strings are often a mix of different ages, an average derating factor of 10% is applied to rated battery capacity (i.e., 90% of rated battery capacity is used) to account for the varying capacities of parallel strings (especially those of different ages).
Customers at Prem sites have the option of less or no battery backup (see Tech Pub
77368 for further information). Backhaul services for wireless can have battery backup reserve time that matches that provided by the wireless company for themselves (in fact, it’s best to get a DC feed from the wireless company so that the cell tower and the backhaul fail at approximately the same time).
DSL and video services may or may not be backed up. When the services are combined on the same circuit packs (such as DSL combo cards, or FTTH sites), the suggested backup time before load-shedding of the broadband loads is 30 minutes. When video services are served from DSL combo cards, that suggested time is increased to 90 minutes.
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Radio sites that are inaccessible during part of the year should have more than 8 hours of battery reserve (determined by the Common Systems Power Planner in consultation with field personnel). Sites solely solar power should have multiple days of battery reserve, depending on the climate.
Lead-acid batteries shall be sized using an end voltage of 1.86 Volts per cell (or 1.17 for
Ni-Cd 38-cell strings in buildings). (For the rare 23-cell VRLA strings or 37-cell Ni-Cd strings, 1.94 Volts per cell must be used for sizing.)
For applications using VRLAs, there shall be a minimum of two strings. This requirement is waived for small RTs and customer prem locations serving 672 or fewer
POTS customers or SONET equivalent customers (unless the circuits are to a government installation, to a nuclear plant, are an FAA circuit, or serve a 911 PSAP site). It is also waived for ADSL and VDSL backup.
Lithium batteries have a current limit linked to an internal disconnect. When sizing a plant using Lithium batteries, it is essential to ensure that a loss of a single battery will not cause the other batteries to exceed their discharge or recharge current limits. In cases of plants where Lithium batteries are paralleled with lead-acid batteries, at points during the discharge and recharge cycles, the Lithium batteries will be supplying or receiving almost all of the current. As a result, sizing must take this into consideration so that the internal disconnect of the Lithium battery is not operated. Paralleling Li-ion strings with lead-acid strings requires the review and approval of a CenturyLink ™
Power Maintenance Engineer, and a signed Letter of Deviation.
Lithium batteries in -48 V plants in COs should use an end voltage of -44.45. In outdoor
RT cabinets, they (and Ni-Cd batteries) can use an end voltage of -44. Batteries are sized such that, given voltage drops, the minimum voltage delivered to CLEC equipment at the end of battery discharge is -42.64 V.
3.9 Battery Stands and Connections
3.9.1 Metal Stands, Trays, and Compartments/Boxes
Metal battery stands are available in a variety of configurations to suit power room applications. The stands are steel finished with acid-resistant paint. Shelves of battery stands for flooded cells should be protected by a non-conductive, acidresistant, plastic sheet under the batteries. The engineer should follow all the specifications pertaining to battery equipment installation to avoid hazardous conditions resulting from abnormal stress, chemical corrosion, or electrical faults.
Large VRLA batteries are generally mounted with the terminals facing forward in large metal powder-coated battery stands. The stand used must be designed for the battery used, installed according to manufacturer instructions, and rated for the
Earthquake Zone in which it is used (an existing stand that is not earthquake rated may be re-used in place if the earthquake zone of the site is 0, 1, or 2).
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Battery trays that mount in heavy-duty relay racks are also made of metal. They must be rated for the weight they will support, and specify the number of screws needed for the weight supported. The shelves should be powder-coated, and may optionally be protected with a non-conductive, acid-resistant plastic sheet.
Very small batteries may mount in a powder-coated metal box that may be wall or relay rack mounted.
In outdoor RT cabinets, batteries are housed in metal trays and/or battery compartments. If housed in sliding drawers, the drawer slides shall be rated for the weight they will carry, and the top clearance between the battery posts and the compartment above shall be at least ½“ (the battery posts should be protected with insulating covers if the clearance is less than 2”). The trays and/or compartments may be powder-coated, and should have a heater pad for climates where the temperatures will regularly drop below 30 degrees F in the winter, and lead-acid batteries will be used. The heater pad should keep the batteries to a temperature of at least 40 degrees F, but not be active at battery or ambient temperatures above 60 degrees F.
All battery stands and relay racks equipped with battery trays that don’t have battery disconnect breakers should be grounded with a #6 AWG ground wire. For battery disconnect breakers (for the purposes of this section, if a breaker does not have overcurrent protection, it is considered a simple disconnect and not a breaker) rated 15 A and smaller, a #14 AWG ground wire to the metal box may be used. For
20 A battery disconnect breakers, a #12 AWG may be used. For 25-60 A disconnect breakers, a #10 AWG may be used. For 70-100 A disconnect breakers, a #8 AWG must be used. For 110-200 A disconnect breakers, a #6 AWG is required as a minimum. For 225-300 A disconnect breakers, a #4 AWG is required for stand grounding. For 350-500 A disconnect breakers, a #2 AWG minimum is required.
For 600-800 A disconnect breakers, a 1/0 AWG grounding conductor is necessary.
For 1000 A disconnect breakers, a 2/0 AWG ground is needed. For 1200 A and larger disconnect breakers, ground the stand with a 4/0.
3.9.2 Round Cell Stands
A modular polyester-fiberglass battery stand is available for use with pure-lead flooded round cells. These types of stand are acid-resistant, fire retardant, and eliminate the possibility of a ground fault or an electrolyte path between cells of widely different voltages. These stands are no longer available (and round cells are no longer manufactured either). Although the stands are not metallic, a #6 AWG ground wire should be run to them to allow a place for a technician to discharge static electricity before working on cells.
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Battery stands must be placed in accordance with CenturyLink ™ Technical
Publication 77351. Single sided battery stands must not be placed closer than 6 inches to any wall, post, or pillar. All other battery stands shall follow aisle requirements stated in CenturyLink ™ Technical Publication 77351. The battery side of two-tier two-row battery stands must not be placed next to a wall; however the end can be placed near the wall using the spacing requirements found in Pub 77351.
Spacing requirements for battery bays (heavy duty relay racks) equipped with
VRLA or Li-based batteries are not covered by Tech Pub 77351 however. These bays do not need rear or side clearance (unless there are side handles or other items on the batteries that require such clearance), although rear access is desirable if the batteries are top terminal batteries installed in a stationary tray. Front clearance for battery bays where the installed batteries will not exceed 85 lbs. each is only required to be a minimum of 2 feet. However, for batteries weighing more than that, 3 feet is the desired minimum front clearance, and 30” is the required minimum.
The majority of battery installation requirements are found in Chapter 10 of Tech
Pub 77350, with some related requirements in other chapters of that installation Tech
Pub.
A minimum of two intercell connectors should be used in all applications where battery posts are designed to accept multiple intercell connectors. The thickness of the connectors should be designed so that the connector(s) will have sufficient strength and flexibility for earthquake zone 4.
All nut and bolt connections made to battery posts, terminal plates, and intercell connectors shall be made with stainless steel (preferred), lead, lead coated copper, or nickel-plated copper.
Intercell connector and all connector lugs connected directly to flooded lead-acid posts shall be lead or lead coated copper. Lead plated connector lugs do not have to have an inspection window. All other lugs should have an inspection skive. Tinplated copper compression type lugs can be used when connecting to the terminal plates and to VRLA, Li-ion and NiMH batteries; however they cannot be used to connect directly to flooded battery posts (lead-plated copper for flooded lead-acid batteries, and nickel-plated copper for flooded Ni-Cd batteries. There will be no connectors varnished, Karo™-syruped or painted, during or after installation.
During activities that could result in an acid spill, including the installation, removal, or rearrangement of batteries, sufficient acid neutralization material shall be on hand to neutralize and contain a minimum of eight gallons of acid for large flooded batteries, or one gallon for flooded engine-start batteries.
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All battery stands shall provide means for anchoring to the floor in order to meet
CenturyLink ™ earthquake Zone standards as required. The CenturyLink ™ approved battery stand anchor shall be used except when shimming is required, or the washer or bolt-head of the battery stand anchor won’t fit the “foot” of the battery stand. The approved CenturyLink ™ toll anchor shall be used when shims are necessary due to uneven floors.
Battery strings should use alpha designations (A, B, C, etc.) going forward (the next battery job is a good opportunity to relabel mislabeled plants). The letters:”O” and
“I” should not be used. If more than 24 strings exist in a plant, label the 25 th string as “AA”, the 26 th as “BB”, etc..
Battery strings are connected in parallel, and individual batteries within a string are connected in series. Individual cells will not be connected in parallel externally; however multiple cell batteries can be connected in parallel within the battery case.
Lead-calcium batteries shall not be reused in another site if the cells are older than 5 years from the manufacturing date on the battery.
New and significantly remodeled battery rooms must conform to the provisions of the Fire Code); be compartmentalized (for lead-acid batteries), and have acid spill containment with sealed flooring (typically epoxy or a linoleum-like acid-resistant material that is epoxied or thermally welded at the seams) if the total free-flowing liquid electrolyte exceeds 1000 gallons (or if so ordered by the Fire Marshal or
Building Inspector). Where containment is necessary, whole room containment is preferred within CenturyLink ™ for multi-string DC plants with flooded batteries in larger offices, however if this is not practical or cost-effective, area containment or individual stand containment are available options. Unless specifically ordered otherwise by the Fire Marshal, neutralization and/or absorptive pillows are not required under the battery stands (they are in the spill kits in the battery area for reactive response). Permanently-placed spill containment pillows shall be Listed for flame-retardancy in NEBS-compliant offices.
The bus bar, auxiliary framing, or cable rack, shall be a minimum of 6 inches directly above the highest point of the battery. No framework, cable racking, bus bars or any other obstruction shall not interfere or impede with the maintenance of the batteries.
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Battery bus bars over flooded battery stands (except the chandelier) may be stacked as long as the following requirements are met. The battery feed bus bar shall be located a minimum of one foot above the cable rack. The battery return bus must be located a minimum of six inches below the cable rack. Battery bus bar shall not be stacked on the same side of the cable rack when above battery stands (however, when not above battery stands, they may be on the same side of the cable rack as long as the vertical separation between buses of opposite polarities is at least 6 inches). When the bus bar is not stacked, the bus bar shall be a minimum of six inches below the cable rack. If there is insufficient room to place the bus bars below the cable rack the battery termination bars may be installed a minimum of four inches above the cable rack.
There must also be a separation of eighteen (18) inches minimum (center line to center line) between the battery and return buses (see Figure 9-5) when they are installed in the horizontal plane by each other.
Sizing of the cables from the bus bar above the battery stand to the main bus bar
(chandelier) shall be in accordance with Chapter 9.
Battery suppliers shall provide a label or stamping on each battery containing the following information:
• voltage
• the rating of the battery at a specific discharge rate, the temperature for that rating, and the end-voltage to which the rating applies
• the minimum and maximum Float voltage
• the operating temperature at which the battery lifetime is guaranteed (e.g., 25 degrees C or 77 degrees F)
• the date of manufacture (may be part of the serial number), preferably in an easily intelligible format
Pilot cells (aka, the Temperature Reference cell) should be in the top tier of the battery stand and have the lowest voltage reading after initial charge of all the batteries on that tier for that string. Cells 1 and 24 cannot be used as the pilot cell.
All VRLA batteries shall have a minimum of ½” spacing between batteries to allow for natural circulation of air, and adequate top clearance (preferably at least 4”) to allow for maintenance. The requirement for top clearance may be reduced to ½” for batteries whose posts/terminals are front-accessible, or when the batteries are in a slide-out tray so that the tops are accessible.
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Chapter 3
Batteries and Battery Stands
Figure 3-1 : Typical Arrangement of Cables for a Flooded Battery Stand
Figure 3-2 : Minimum Dimensions for Bus Bar above Flooded Battery Stands
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3.10 Battery Disconnects
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Issue K, July 2015
A disconnect breaker or other means to disconnect the battery (e.g., quick-disconnect plug, or a switch) shall be connected in series with each VRLA string (and is required as part of the built-in protection for Li-ion batteries – size designed by the Li-ion pack manufacturer) that is not in a CO or microwave radio site. Battery disconnects may also be required by a Fire Marshal, or when battery cables are not separated from fused cables on an unfused rack (in that case a fuse or breaker is required). The breaker or disconnect shall be large enough to handle recharge capacity. When the Fire Marshall requires the installation of Battery Disconnects for each string of and/or an Emergency
Power Off (EPO) switch, the EPO switch will disconnect the batteries, Engine, and AC
Service. This requires the installation of a battery disconnect with shunt-trip capability.
Battery cabling voltage drop standards are in Chapter 9. The disconnect is sized at the
125% of the 2 hour battery discharge rate (for an end point cell voltage of 1.86 for leadacid cells). The 2-hour rate rule only applies to long duration (3 hour or more designed discharge times) applications.
Note that after the voltage drop calculation is completed, the cable size suggested by that calculation should be compared to the ampacity of an overcurrent protection device (where one exists), and it is suggested (although not absolutely required in
CenturyLink-owned buildings) that the ampacity of the cables meet or exceed the protector size (when the disconnect is a breaker or fuse). In space that is not owned by
CenturyLink, if the battery disconnect also happens to be a breaker or fuse, by Code, the ampacity of the cables must equal or exceed the protector (fuse or breaker) size.
The following calculation examples apply to Table 3-1:
• 4000 Amp-hr Mini Tanks are rated at 927 Ampere-hours at the 2-hour rate, therefore 927A × 125% = 1158.75 Amperes. That indicates the need for a 1200
Ampere battery disconnect. Three 750 kcmil cables are the minimum suggested number of cables (the ampacity of each 750 kcmil cable is 475 Amps). This exceeds the minimum of four 350 kcmil cables required by Chapter 9. Voltage
Drop calculations (per Chapter 9) may require more cables.
• 1680 Amp-hr type batteries are rated at 415 Amperes at the 2-hour rate, therefore
415 × 125% = 519 Amperes, which indicates the need for a 600 Amp battery disconnect. Two 350 kcmil cables are the minimum number of cables suggested
(cable ampacity of 350 kcmil cable is 310 Amps) based on this calculation, but
Chapter 9 requires four 4/0 AWG cables or equivalent as a minimum. Voltage
Drop calculations (per Chapter 9) may require more cables.
Note that for all 3 long duration battery disconnect sizing tables, most of the values are approximate, and will vary by manufacturer and model.
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Chapter 3
Batteries and Battery Stands
Table 3-1 Typical Battery Disconnect Sizes for Long-Duration Flooded Lead-Acid
Amp-hr
Rating to
1.75 V/cell
110
155
200
270
360
420
450
540
660
720
840
1008
1176
1344
1680
1810
2016
2110
2320
3344
3623
3900
4000
Amps @ 2 hour rate to
1.86 V/cell
30
43
54
66
88
102
110
132
157
175
208
246
287
328
415
441
491
544
619
795
852
907
927
Amps @ 4 hour rate to
1.86 V/cell
19
28
35
45
60
70
75
91
110
121
140
170
199
227
280
306
341
366
409
554
600
639
653
Amps @ 8 hour rate to
1.86 V/cell
12
17
22
29
39
45
48
58
71
77
91
108
126
144
181
194
216
223
243
354
384
409
418
125 % of the 2 hour rate
138
165
196
219
260
308
359
38
54
67
83
110
128
774
994
1065
1134
1160
410
519
551
614
680
Table 3-2 Typical Battery Disconnect Sizes for Ni-Cd Batteries
Minimum
Disconnect in
Amperes
40
60
70
90
110
150
150
175
200
225
300
350
400
800
1000
1200
1200
1200
450
600
600
700
700
Amp-hr
Rating to
1.0 V/cell
75
100
140
175
Amps @ 2 hour rate to
1.17 V/cell
25
32
45
55
Amps @ 8 hour rate to
1.17 V/cell
9
12
17
21
125 % of the 2 hour rate
32
40
56
69
Minimum
Disconnect in
Amperes
35
40
60
70
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Table 3-3 Typical Battery Disconnect Sizes for Long-Duration VRLAs
Ah Rating
@ 1.75
V/cell
80
90
100
110
125
145
150
155
170
180
190
570
760
950
1045
1425
1520
2000
3000
25
30
45
60
70
5
7
9
12
18
Amps @ 2 hr rate to
1.86 V/cell
29
35
39
43
45
53
54
56
62
65
70
183
237
299
336
449
488
627
940
11
12
17
24
26
1.9
2.7
3.1
4.9
6.5
Amps @ 4 hr rate to
1.86 V/cell
16
19
21
23
26
29
30
31
35
37
40
110
146
189
201
283
293
371
556
5.8
6.5
10
14
15
1.1
1.5
1.7
2.5
3.5
Amps @ 8 hr rate to
1.86 V/cell
9.1
10
11
13
15
17
18
19
20
22
23
60
86
113
119
169
173
227
340
3.0
3.5
5.4
7.5
8.0
0.6
0.8
0.9
1.3
1.9
125 % of 2 hr rate
36
44
48
54
56
66
68
70
78
81
88
229
14
15
24
30
33
2.4
3.4
3.9
5.9
7.9
296
374
420
561
610
784
1175
Minimum
Disconnect in Amps
40
45
50
60
60
70
70
70
80
90
90
250
300
400
450
600
700
800
1200
15
15
25
30
35
3
5
5
6
10
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Chapter 3
Batteries and Battery Stands
There are a few scenarios that differ from the standard design already covered.
• Excess Rectifiers. This scenario has the possibility of providing more current to the batteries than even the two-hour charge rate. Obviously, this may operate the breakers, but excess rectifiers are the main cause of thermal runaway, and this is one of the reasons to place the breakers in series with the batteries. The recommendation in these cases is not to upsize the breakers, but to shut off excess charging capacity.
• Excess Battery Capacity with Large Cells (cells with large Amp-hour ratings require fewer strings). Excess rectifiers coupled with this scenario could be a problem, because the large cells mean that fewer strings are necessary. Another scenario is that the breaker sizing, based on the large Amp-hr rating of the cells, would exceed the total charging capacity of the plant. For example, a 540 Amphour VRLA cell used in a 100 Ampere plant with three 50 Ampere rectifiers would call for a breaker rated at 200 Ampere. However, the total charging capacity of the plant is only 150 Amp-hours. Although a disconnect breaker (if a thermal-magnetic breaker is used as the disconnect) will never trip on charging, it can still be useful as a maintenance tool for manually disconnecting the string
(and magnetic breaker will still also protect against short circuit currents).
For UPS type applications, the battery disconnect must be sized at a minimum of 125% of the expected maximum discharge current. This current can be calculated from the following formula:
Where,
I max
is the maximum DC current that would be drawn from the battery of a fully-loaded UPS at the inverter minimum operating voltage
R
VA
is the rating of the UPS in Volt-Amps (if the unit is rated in kVA, multiply that kVA value by 1000 to get the Volt-Amp rating) mvpc is the minimum volts per cell design of the battery, based on the inverter minimimum operating voltage, and the number of cells in series per UPS battery string n c/s
is the number of cells (nominal 4, 6, 8 and 12 V monobloc lead-acid batteries have 2, 3, 4, and 6 cells per jar, respectively, and all cells must be counted) per string (note that many UPS have multiple strings in parallel for reliability reasons, but that for this calculation, only the number of cells in a single string is used)
η is the conversion efficiency of the inverter when the UPS is fully loaded
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The typical design mvpc for most North American UPS lead-acid battery systems is
1.67 V. Most modern UPS have maximum inverter conversion efficiencies of at least
95% ( η ≥ 0.95). Substituting these two values yields the following simplified equation for UPS lead-acid b attery maximum current:
The simplified equation can be used to perform a sample calculation, as follows:
• For an 80 kVA UPS, there are forty 12 V VRLA monoblocs per string. This means that for purposes of the equation, R
VA
is 80,000 (1000 x 80), and n c/s
is 240 (6 x 40).
Plugging the numbers into the formula yields a maximum current of 210 Amps.
Multiplying this number by 125% gives a value of about 263 Amps. Upsizing to the next standard size breaker means a battery disconnect size of 300 Amps.
Even when there are parallel strings on the UPS, the user would want to protect each string with a DC-rated breaker of at least 300 Amps in case of open circuits in parallel strings during operation or testing.
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Chapter 4
Converters (DC/DC)
Chapter and Section
4.
CONTENTS
Page
Converters ................................................................................................................... 4-1
4.1 General ............................................................................................................. 4-1
4.2 Alarm Features ............................................................................................... 4-1
4.3 Technical Requirements ................................................................................ 4-1
4.4 Line Powering................................................................................................. 4-3
4.4.1 Introduction to Line-Powering .................................................. 4-3
Nominal Line-Powering Voltages ............................................. 4-3 4.4.2
4.4.3
4.4.4
4.4.5
4.4.6
4.4.7
4.4.8
4.4.9
Pairs and Wire Gauges Used in Line-Powering ...................... 4-4
Line-Powering Current and Power Limits ............................... 4-6
Transmission Power Loss ........................................................... 4-7
Human Susceptibility Thresholds for Voltage and Current .. 4-8
Safety Precautions and Access for Line-Powering Voltages
Above 60 ........................................................................................ 4-9
Current-Limiting of Higher Voltage Ground Faults ............ 4-10
Additional Operational Concerns for Operation Above
300 VDC Across the Pairs ......................................................... 4-11
Tables
4-1 Recommended Voltage Operating Windows for Line-Powered Equipment .... 4-4
4-2 Resistance and Ampacity of Common Sizes of OSP Copper Pairs ..................... 4-5
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4. Converters (DC/DC)
Chapter 4
Converters (DC/DC)
4.1 General
This unit covers DC/DC converters that transform the output of a rectifier/battery plant. The converter output voltage may be higher, lower, or at a different polarity than the input voltage. In some special cases, where ground, noise, or transient isolation is required, the output voltage and polarity may be the same as the input.
Converters can be applied in two ways: as bulk converter plants or as imbedded
(dedicated) converters. Imbedded plants are generally provided as a component of the served equipment. The requirements of this unit apply to bulk converter plants.
If the capacity of the converter plant is exceeded for any reason, the output voltage of the converters must be lowered rather than allowing the plant to fail.
PLANT SIZING — Converter plant size is based on the peak loads of the connected equipment. In other words, sufficient converter capacity must be provided for possible short-term peaks.
WORKING SPARE — The number of converters in a plant should be at least one more than is required for the total anticipated current drains defined above, so that the failure of any one converter does not overload the remaining converters.
Collocators may install DC-DC converters in their space (fed from CenturyLinkprovided DC feeds) with the permission of CenturyLink. However, these converters may not have batteries or fuel cells connected to their output bus as a backup DC source. Customer-provided converters must meet NEBS ™ Level 1 (see Section 1.6) for
NEBS ™ spaces. For non-NEBS ™ spaces, the converters must be Listed.
4.2 Alarm Features
The following converter plant alarm indications are minimum alarming considerations
(the alarms noted in the combined major and minor alarms may be broken out individually). Alarms provided should include the ability to be wired to local audible and visual alarm systems as well as the remote alarm system.
• MINOR — One converter failed: A single converter failure (as opposed to being turned off) will initiate a minor alarm.
• MAJOR — Converter majors include plant distribution, or control fuse/breaker operation, low bus voltage, high bus voltage, and two or more converters failed.
4.3 Technical Requirements
Protection (fuses or circuit breakers) for feeds from a converter plant shall NOT exceed the capacity of the plant minus the spare converter.
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Converters (DC/DC)
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Individual Converters should have individual power feeds, rather than a single power feed to the Converter Plant. If there are feeds common to more than one converter, the combined total size of the converters served by the common feed becomes the “spare converter” size.
Converter output voltage static regulation shall be ±1% over a load range of 10% to full load.
Converter input voltage range shall be at least -42 to -59 VDC for nominal -48 Volt input, and ± 21 to ± 29.5 VDC for nominal ± 24 Volt input.
The converter case and/or shelf shall contain an adjustable high voltage shutdown circuit that automatically shuts itself down when the output voltage exceeds a preset value. When this occurs, a low voltage alarm indication shall be given as a minimum.
The converter output current shall be limited to no more than 110% of its rated capacity.
The converter output voltage shall be adjustable to ±10% of its normal output voltage.
The converters plant shall have meters displaying the output voltage and current.
Analog current meters shall have a scale with a range of 150% of the rated capacity. The converters should have either a meter or LED bar graph to display the load current.
They should also have test jacks to measure converter voltage.
All components of the plant and converters shall be removable through front access.
The converter equipment shall be modular. During growth and additions, the delivery of power to the using systems shall be maintained.
All converter equipment shall have a nameplate with a minimum of the supplier's name, model and serial numbers, input and output voltages, and manufacturing date.
For loads with a different voltage and/or polarity than the primary battery plant, two choices exist to serve them:
• Converter plant
• A separate Battery plant
For loads less than 100 Amperes, typically a converter plant is the preferred option. For loads exceeding 100 Amperes, typically it is less costly over time to serve those loads with a new battery plant at their voltage and polarity. The engineer should evaluate the economics before making a decision.
Step-up converters are considered separately derived DC power sources by Code. This means that in addition to the frame grounding, the output return bus of the converter plant must be directly referenced to a COGB, PANI MGB, or OPGP (see CenturyLink ™
Technical Publication 77355, Section 5.5). Step-down converters may or may not be separately derived. If they are separately derived, they are typically described as
“isolated”.
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4.4 Line-Powering
Chapter 4
Converters (DC/DC)
4.4.1 Introduction to Line-Powering
Line powering (including express/span powering) is the use of twisted pair copper
(AWG 19-26) to pass DC power from a source in a building/cabinet to an RT or housing (the powering may be from headend to a remote end, or “back-powering”).
Telecommunications networks have a long history of using line powering for various tasks, such as the coin return mechanism of payphones, T-1 repeater powering, HDSL remote unit powering, FTTC powering, etc. Line powering remains popular for existing and emerging technologies because it doesn’t require placement of power company meters, rectifiers, and batteries at remote locations.
Even though power is wasted (I 2 R losses) in the transmission of line power, it is still often more cost effective for relatively small wattage needs compared to placing AC power and associated power-conditioning equipment at the remote end.
Line-powering voltages commonly found in the industry and addressed by
Telcordia ® NEBS ™ document GR-1089, ITU-T recommendation K.50, and UL ®
Standards 60950-1 and 60950-21 are less than 200 V with respect to ground (e.g., nominal -48 VDC, -130, -190, ±130, ±190, etc.).
Line-powering voltages are either positively ground-referenced (e.g. – 190 VDC), or bipolar center-tap grounded (e.g., ±130, ±190 VDC). Negative voltage on the energized conductor(s), such as a nominal -130 V system, limits corrosion of the copper pairs when water intrusion occurs in Outside Plant cables.
In addition to the information on line-powering in the above-referenced documents, there are maximum power and current limits in the NEC ® and NESC; maximum voltage, power, and current limits in ANSI/ATIS-0600337; and additional electrical protection information for line-powering schemes in ANSI/ATIS-0600332.
4.4.2 Nominal Line-Powering Voltages
There are many historical systems that have used line-powering (both voltage and current-based), such as T-1, HDSL, payphone coin return, etc. Their voltage windows, current levels, and power usage vary based on the system and manufacturer. The purpose of this section is to define line-powering circuit characteristics (e.g., voltage windows, power maximums) for non-MDed existing and going-forward systems, rather than cover all of the legacy systems. This does not preclude the use of other voltages and systems, but allows for interoperability of systems meeting these guidelines.
The recommended voltage windows for line-powering are summarized in Table 4-1.
Whenever possible, negative uni-polar voltages (e.g., -48, -130, -190 should be used to minimize the corrosion of copper pairs.
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Table 4-1 Recommended Voltage Operating Windows for Line-Powered Equipment
Nominal
Line-Powering
Source-End
Voltage
-48 VDC 2
-130 VDC
±130 VDC
-190 VDC
±190 VDC
1
1
Minimum Voltage
Operating Window for the End-Use Equipment
-30 to -56
-70 to -140
±70 to ±140
(140 to 280 across pairs)
-100 to -200
±100 to ±200
(200 to 400 across pairs)
Extended
Maximum
Operating Voltage
-60
-150
±150
(300 across pairs)
N/A (-200)
N/A (±200)
Extended
Minimum
Operating Voltage
-27
-65
±65
(130 across pairs)
-95
±95
(190 across pairs)
Notes:
1.
Any voltage on a copper pair exceeding 140 V (positive or negative) to ground must have fast-acting source current-limiting (to 10 mA or less) when a ground fault is detected
2.
The -48 VDC line-powering source referenced here excludes legacy POTS circuits, and PoE within a building.
4.4.3 Pairs and Wire Gauges Used in Line-Powering
Line powering can be done over the data transmission pairs, spare pairs (often referred to as “express powering”), or both. While 24 AWG and 26 AWG are the most common wire sizes in typical OSP distribution, some 22 AWG has been deployed specifically to enhance broadband bandwidths. If 19 AWG exists in the
OSP, it is usually deployed primarily for line-powering applications to extend the reach (19 AWG has approximately half the resistance of 22 AWG).
Line-powering over distance often requires more than 1 pair (bonded at both ends), depending on the wire gauge used for the transmission, the end power requirements, and the equipment operating voltage window.
In a line-power system, an equipment manufacturer-supplied calculator is typically used to determine the number of pairs needed so that the minimum end voltage of the equipment is met. However, to calculate it manually, the following information must be known: the max expected operating temperature (higher temperatures increase the cable resistance – note that aerial cable will typically operate hotter than buried cable), the cable gauge(s) and their resistance (typically given per kft) at the expected maximum operating temperature, the number of available parallel pairs, the maximum power usage (in watts or constant current amps) expected at the enduse equipment, and the minimum operating voltage of the end-use equipment.
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Chapter 4
Converters (DC/DC)
The resistivity of copper (IACS) is an SI-derived unit, and is approximately
1.721 x 10 -8 Ω· m at 20°C (68°F). Over normal operating temperature ranges, the coefficient of resistivity for copper is approximately 0.393%/°C (≈ 0.218%/°F). The following Table (4-2) gives some baseline values of twisted pair resistivity at various temperatures, which can be adjusted for the expected maximum temperature based on the coefficient values given in the preceding sentence.
Table 4-2 Resistance and Ampacity of Common Sizes of OSP Copper Pairs
Wire Size circular diameter Ampacity Ω/kft/pair at various temperatures
26
24
23
22
20
19
254
404
509
642
1020
1290
0.0159
0.0201
0.0226
0.0253
0.0320
0.0359
0.8
1.3
1.5
2.1
3.0
4.2
84.6 86.3
53.2 54.3
42.2 43.4
33.5 34.2
21.0 21.6
16.7 17.0
94.7
59.5
47.3
37.4
23.5
18.7
99.6
62.6
49.7
39.4
24.7
19.7
103.0
64.7
51.5
40.8
25.6
20.3
Note: the resistances are approximate and are those of the complete circuit created by a pair of solid un-tinned soft annealed copper wires (e.g., the resistance of 1 kft of a 26 AWG copper pair is actually the resistance of 2000 ft of 26 AWG copper conductor)
If the far-end equipment is constant current, use the cable resistances at maximum expected operating temperature and Ohm’s Law to calculate the voltage drop.
If the far-end equipment is constant power (much more common than constant current for modern line-powered equipment) use the minimum operating voltage of the equipment, divided into its maximum watt draw, to determine the maximum operating current. This current can then be plugged into Ohm’s law to determine the voltage drop. If the voltage drop from the source normal operating voltage
(which will typically be the nominal voltage or slightly above it, but typically not quite as high as the maximum from Table 4-1) drops the far-end equipment operating voltage below its window (see Table 4-1), then more pairs must be used.
Add pairs until the resistance decreases enough (2 parallel pairs of the same gauge are half the resistance of a single pair, 3 parallel pairs is a third of the resistance, etc.) that the voltage window is met at the far end. Note that the equipment (both source and far-end) may be limited in the number of pairs it can accept.
The following equation condenses the text of the paragraph above in order to determine the number of pairs needed for end-use equipment that is relatively constant power:
4-5
Chapter 4
Converters (DC/DC)
PUB 77385
Issue K, July 2015 where;
N
R d k p is the minimum number of pairs needed p/k
is the loop resistance per kft for the wire size to be used at the expected maximum temperature is the one-way distance (in kft) from the source to the use end of the
P max
V min line-powering circuit
is the maximum power usage of the end equipment
is the minimum voltage at the end equipment
4.4.4 Line-Powering Current and Power Limits
The NEC, the NESC, UL ® 60950-21, and GR-1089 limit the amount of power that can be transmitted per each twisted pair circuit (i.e., the bonded multi-pair circuit, not just per pair) to 100 VA (which is 100 W in DC terms). In practical terms this means that the user does not have to worry about exceeding the ampacity of the twisted pair since for all of the nominal line-powering voltages listed above (except for nominal -48 VDC), the current will be less than the 1.3 Amp maximum specified by some standards. The NEC ® also limits current to 100/V max
for continuous current and 150/V max
for short durations. This will not cause an issue with nominal linepowering voltages of 130 and higher; however, it may cause an issue with nominal
48 V line-powering. For nominal -48 VDC circuits drawing between 1.3 and 2.4 A, multiple pairs may need to be used (except for 19 AWG) to ensure the ampacity of the smaller gauge twisted pair wire is not exceeded; and the connectors must be rated for the higher current.
The 100 W source limit also imposes a practical limitation of about 50 W (although this can be exceeded with enough pairs, shorter distances, etc.) on the served equipment circuit (since it is expected that up to half of the source end power, or up to 50 W, will be lost through I 2 R cable losses – see section 4.4.5). For line-powered equipment that needs more than 50-75 W, the common method has been to use multiple 100 W maximum line-powering twisted pair circuits feeding individual
DC-DC converters at the equipment end. Those converters usually step down the voltage to nominal -48 VDC and parallel the converter outputs, since there is no 100
W limitation on the power circuit at the user end (the limitation is on the power that can be transmitted on twisted pair telephony wires).
While 100 W is the max source limit per twisted pair circuit, if the end equipment needs much less power, it may be more economically efficient to source a power supply with capabilities matched more closely to twice the load power requirement.
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Many central office 5-pin protectors have a heat coil or PTC resistor that effectively limits the current on a single pair to 150 mA (older versions) or 350 mA (newer versions). Applying the nominal 125% protector sizing rule (see NEC ® Article
210.20A, for example), this means that each pair out of a CO should probably carry no more than 120 or 280 mA, depending on the type of protector for that pair at the frame. When more current is needed, pairs must be multipled or the line-powering voltage must be stepped up (to a max of nominal ±190 VDC) to lower the current on the individual pairs. Overvoltage protectors in RTs do not commonly have heat coils or PTCs, so there is usually no 120 mA limitation to pairs leaving an RT site for line-powering purposes.
When the manufacturer of the near end line-powering equipment differs from the manufacturer of the power supply(ies) at the far end, extensive lab testing may be necessary to ensure compatibility, especially at “turn on” due to capacitor charging, slew rates, etc.
4.4.5 Transmission Power Loss
While a wider voltage operating window suggests more I 2 R losses in the transmission, it also suggests that more power was transmitted over the fewest number of possible pairs.
In a typical scenario for line-powering (as defined by the voltage windows of Table
4-1), up to half the power is lost in the transmission (the voltage at the end is also half of what it was at the source). This also works well with DC-DC converters that are found at the end of a line-powering loop, since many “brick” DC-DC converters have a bottom of the voltage window that is exactly half their maximum input voltage.
Because the design of the line-powering circuit is with worst-case draw of the enduse equipment, most equipment will lose less than half the power in the transmission, since the actual normal draw of the equipment is often much less than the maximum due to fill rates and usage patterns.
There are many applications where more than half the source end maximum power is used in the end equipment being powered (e.g., an end-use ONU on a nominal -
130 VDC circuit drawing a peak of 74 W, which leaves only 26 W to be lost in the transmission pairs). What this means is that more pairs will have to be used than in a circuit that shares the power equally between transmission and end-use in a maximum draw scenario.
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4.4.6 Human Susceptibility Thresholds for Voltage and Current
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Through testing, various voltage and current thresholds (in conjunction with contact time) have been established as “cross-over” points for human shock and safety.
While standards and other documentation on the subject disagree slightly on exact current and voltage levels, due to test methods, differences in subjects, etc., generalizations can be made.
Current through the body determines the severity of a shock. For DC, the following generally applies:
• 2-30 mA may possibly be felt as a slight shock or tingle, but no harmful effects occur
• 30-100 mA can produce mild shock and muscle paralysis
• 100-300 mA can cause severe pain and trouble breathing
• Currents through the body greater than 300 mA can stop breathing and cause cardiac arrest
Current levels are typically determined by the voltage, the current path through the body, and the resistance of the body. Depending on the path through the body and the individual person, the typical resistance of the human body ranges from 20,000 to 1,000,000 ohms. However the resistance of a wet or sweaty human body (or the resistance through an open wound since the skin is the most resistive element of the body) can be as low as 500-2,000 ohms.
The following DC voltage levels represent thresholds relevant to this document for differing physiological effects with human body resistance as described by the currents and resistances in the preceding paragraphs (they do not cover the increased danger to humans as voltage increases from arc flash and arc blast events associated with inadvertent metal contact):
• Below 60 V is generally classified as “safety - extra low voltage”, and will have little effect on a body (unless it is wet or has open wounds)
• 60-150 V can produce a mild shock and muscle paralysis
• 150-300 V can cause severe burns and ventricular fibrillation
• Voltages above 300 V can stop breathing and cause cardiac arrest
The voltage levels in the bullet points above can be to ground when one hot conductor is contacted and the current path is from the contact point through the feet or other grounded body point, or they can be across the body when two hot conductors are contacted at separate points (such as inadvertently holding a +190 V tip conductor in one hand and a -190 V ring conductor in the other).
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Very short duration (in the microsecond, nanosecond, or shorter range) pulses (such as those used by police in non-lethal weapons) or transient events of extremely high voltage or currents above the top levels given here may not be lethal (even though they are quite painful) because they are not long enough to cause fibrillation or excessive internal body heating. Line-powering schemes exist (although not in wide use) using relatively higher pulsed voltages in order to avoid the greater personnel dangers, but take advantage of the power transfer efficiencies of higher voltages.
4.4.7 Safety Precautions for Line-Powering Voltages Above 60
All of the line-powering voltages discussed here are classified as A2 or A3 by
Telcordia ® GR-1089, and must be appropriately marked for the hazard, and protected against accidental contact where possible at all appearance points along the circuit (especially at the source and use ends).
Accessibility requirements should be based on the voltage level and on the training level of personnel who are expected to contact, or who might accidentally contact, these voltages. Two levels of training are identified in standards: trained and untrained . Trained persons are individuals who are knowledgeable and experienced in working on energized telecommunications circuits. Such persons are typically technicians employed by telecommunications companies to install, repair, and maintain telecommunications equipment. Untrained persons are those who are unfamiliar with the principles of electricity and have little or no knowledge of electrical circuits. Such persons may be customers utilizing telecommunications services.
Class A3 voltage sources shall be inaccessible for contact by untrained persons. Class
A3 voltage sources shall have restricted access for contact by trained personnel. If it is exposed for contact by trained personnel, it shall comply with the following precautions.
• Baffling and Segregation : When an enclosure or baffle is removed, or energized electrical circuits are otherwise exposed for contact by trained personnel, Class
A3 sources shall be segregated from lower voltage A2 sources by appropriate insulation, baffling, or location to prevent inadvertent contact
• Labeling : Designed appearances of Class A3 voltage sources on equipment that is powered by or that generates such voltages shall be labeled where trained personnel are normally intended to contact them for service or repair
Determination of accessibility should be done by the equipment manufacturer based on the intended application.
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The following minimum safety precautions should be taken when working on linepowering circuits covered in this document:
• Storm conditions – Do not work on exposed plant during a thunderstorm
• Temporary bonds – When work operations require such activity as opening a cable shield, place temporary bonds as appropriate to minimize potential differences caused by a temporarily discontinuous path to ground
• Insulated tools – Use only hand tools with insulated handles
• One conductor at a time – Whenever possible, work on only one conductor of a pair at a time; which prevents contact with the higher voltage between two conductors in ± line-powering system
• Small, dry contact area – Keep the area of the skin in contact with a conductor as small and as dry as possible (resistance of the skin is directly proportional to the area of skin contact and inversely proportional to the moisture content of the skin)
• Contact with ground – Avoid simultaneously contacting a grounded object with part of your body while handling bare conductors (dry footwear will provide some insulation from ground)
• Training – Service personnel working on line-powered systems shall be properly trained to work on such systems
UL ® 60950-21 and ATIS-0600337.2010 do not permit communications circuits in excess of TNV limits (60 VDC) past the service provider’s point of demarcation.
4.4.8 Current-Limiting of Higher Voltage Ground Faults
For safety purposes, -145, ±145, -190 and ±190 VDC line-powering sources must be current-limited to 10 mA if a ground fault is detected from a “hot wire (either tip or ring). That said, there is generally no such protection if a technician gets across the positive and the negative of a ±145 or ±190 circuit. This means that the current through a technician on such a 100 W current-limited circuit could be as high as 500 mA (but more usually maxing out at 250 mA), depending on their body resistance at the moment of contact, and how far from the twisted pair circuit source end they are located (voltage drop across the pairs to that point). For this reason, technicians should always be careful when dealing with any line-powered circuit, but especially careful with ±190.
Note also that the ground fault detection circuit required for circuits over 140 V to ground can cause nuisance tripping and resets if not properly tuned.
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4.4.9 Additional Concerns Above 300 VDC Across the Pairs
Chapter 4
Converters (DC/DC)
In addition to the aforementioned safety precautions for nominal ±190 VDC circuits, existing older cable pairs must be tested with a meg-ohmmeter to ensure that there is no insulation breakdown (some older OSP cable may not be capable of more than
300 V due to age-induced insulation breakdown), nor operation of TLPU protectors when ±190 VDC is applied (some protectors are designed to “fire” around 300 V).
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Chapter 5
Inverters (DC/AC)
CONTENTS
Chapter and Section
5.
Page
Inverters (DC/AC) ..................................................................................................... 5-1
5.1 General ............................................................................................................. 5-1
5.2 Inverter Selection ........................................................................................... 5-2
5.3 Load Classification ......................................................................................... 5-2
5.4 Alarm Features ............................................................................................... 5-2
5.5 Technical Requirements DC and AC Power Supplies .............................. 5-3
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5. Inverters (DC/AC)
Chapter 5
Inverters (DC/AC)
5.1 General
Inverters change DC to AC at a voltage suited to the load, and although they are often truly uninterruptible, they are not classified as a commercial UPS. Inverters are more reliable than a standard UPS and may be of the solid state or rotary type.
Two basic configurations are provided:
• Standby — in the standby configuration, the AC input powers the load directly and the inverter is a source of backup power. This operating mode conserves the life of the inverter and conserves energy. However, the incoming power is untreated so the load must be able to tolerate any power line disturbances that may be present. This mode is also known as AC-preferred.
• ON LINE — in the on line configuration, the inverter usually operates off the DC source to power the load, and the AC source, (if available) is the backup power.
The on line option is preferable. This mode is also known as DC-preferred.
Online is the preferred configuration. An automatic static transfer switch is often provided to switch to commercial AC in case of an inverter failure. A maintenance bypass switch must be provided. The maintenance bypass and AC feed with its static transfer switch are not required in LNS when the inverter has redundant power modules that can carry 100% of the load (eliminating the need for maintenance bypass) during the service or replacement of a failed inverter module.
Components of the inverter shall be front-removable.
Inverters shall be modular to facilitate growth. Maintainability shall be stressed in the design. The design shall allow repair by module replacement.
Inverter nameplates shall contain the following information as a minimum: Supplier’s name, inverter model number, inverter serial number, and manufacturing date.
The following equipment should generally be connected to an inverter if it is found in a larger Network site and uses AC power:
• Switches or other Network equipment that should have uninterrupted service and that require AC power.
• Computers essential to switch operation. Typically, no more than 2 maintenance terminals need to be powered from inverter protected AC. No printers or personal computers are permitted on the inverters.
• 911 equipment that is not DC powered.
• Fire Alarm panels.
• Card Entry Systems.
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• Task lighting (as an alternative to DC-powered lighting for these applications).
• Switch room telephone systems (key systems, wireless systems, etc).
• Outlets serving modems essential to network elements.
• Outlets serving devices installed in frames that control or are essential to the operation of equipment serving over 1400 DSO’s and/or any DS1’s or DS3’s
(DISC controllers, TLS controllers, etc).
• The circuit shall be identified that it is inverter powered by a permanent label at the point of termination.
As implied in Chapter 1, unless specified in the individual contract, CenturyLink ™
National Network inverters may not power CLEC equipment (in the CenturyLink ™ local Network they are allowed to do this under state rules, tariff or contract).
Uninterruptible AC power provided by an inverter is expensive (due to the high cost of the inverter, and the battery backup and rectifiers required to support it). Non-critical and non-network loads should not usually be placed on the inverter. The Common
Systems Power Engineer and the Power Maintenance Engineer are the final arbiters if there is disagreement over whether to place certain types of equipment on the inverter.
5.2 Inverter Selection
Inverter plants must be selected to have proper characteristics and designed to be compatible with the equipment served.
For inverters operating in a Stored Program Control System (SPCS) environment, all loads must meet the grounding requirements described in Chapters 4, 8, and 9 of
Technical Publication 77355.
Any CenturyLink ™ load requiring backup that can be DC-powered generally should be
(especially in sites that already have a DC power plant), even if the power supplies cost a little more. In sites with a DC plant (or more than one DC plant) with equipment that does not have a DC-powered option, an inverter plant powered off a DC plant is the first choice when the total AC loads in the site/area that require uninterruptible power are less than 60 kW. For larger total uninterruptible AC loads, or for a site that does not have a DC plant, a commercial UPS (see Chapter 6) may be the choice.
5.3 Load Classification
Inverter plants are always classified as an "essential load” for sizing standby AC.
Inverters are also included as part of the "power fail load" for sizing the feeding DC plant batteries when the inverter is operated in the continuous "on line" mode.
Inverters must be included as part of the "busy hour" load for sizing the DC plant.
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5.4 Alarm Features
Chapter 5
Inverters (DC/AC)
The following alarm indications shall be provided for local and/or remote surveillance:
• Inverter "fail" — an inverter has failed.
• Inverter "supplying load" — a status indication used as an AC power failure indication for inverters normally operated in AC-preferred mode.
All points, loads, and alarms shall be accessible for connection to a Power System
Monitor Controller (PSMC). The inverter shall produce alarms as described herein and in Chapter 8.
Each fuse shall be provided with a blown fuse indicator connected to an alarmindicating lamp on the control panel.
5.5 Technical Requirements
The inverter shall be capable of tolerating power factors as low as 0.8 (80%) leading or lagging without damage to the inverter.
Multi-phase inverters shall be able to operate with a line-to-line load imbalance of 20 percent or greater without damage to the inverter
All external metal parts shall be grounded, and the grounding requirements of
CenturyLink ™ Technical Publication 77355 shall be met.
The inverter shall have built-in protection against under voltage, overcurrent, and over voltage.
Inverters shall be capable of being mounted in 19" or 23" racks, or in a floor-mounted cabinet.
An n+1 inverter configuration should be considered for critical loads and in high profile offices. N+1 inverter bays or shelves shall be designed so that the parallel inverters remain synchronized in their AC waveform in case of a bay/shelf controller failure.
Inverters may be separately derived power sources and shall be equipped with a grounding bus, and a neutral bus on the output. These buses should be grounded and bonded in accordance with CenturyLink ™ Technical Publication 77355, Sections 5.5 and
4.2 (which follows NEC ® Code requirements for separately derived sources). A simple way to tell if an inverter is separately-derived is if it has a hard-wired AC neutral that passes through and/or around the inverter (single line drawings of the inverter may be needed to determine if the internal AC neutral is hard-wired – not switched in the static transfer switch). If an inverter is only fed by DC, it is guaranteed to be separately derived.
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Chapter 6
Uninterruptible Power Supplies (UPS)
Chapter and Section
6.
CONTENTS
Page
Uninterruptible Power Supplies (UPS) .................................................................... 6-1
6.1 General .............................................................................................................. 6-1
6.2 Definition of Terms ......................................................................................... 6-1
6.3 Technical Requirements ................................................................................. 6-3
6.4 Alarming and Control .................................................................................... 6-5
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6 Uninterruptible Power Supplies (UPS)
Chapter 6
Uninterruptible Power Supplies (UPS)
6.1 General
This unit outlines general engineering considerations for Uninterruptible Power
Supplies (UPS).
UPS require cooling of the ambient air to allow for full output and longevity of components. UPS equipment areas should be designed with the same environmental considerations as other equipment locations containing batteries.
The air in the room containing the UPS batteries must be exchanged a minimum of one complete change per hour to relieve the accumulation of battery fumes. If the batteries are located in an enclosed cabinet, that cabinet must be ventilated to the outside room at a minimum of one complete air change per hour. Local codes may require a higher rate of air exchange.
Larger UPS may induce extreme floor loading due to the combined weight of the system components. The loading factor may require the engineering of special floors.
Some systems may require reinforced raised floors so that cool air can be introduced under the floor.
A UPS system must be engineered to be as reliable as the system it serves. As such, the manufacturers’ recommendations for installation must be followed. This unit is an engineering guide for UPS systems that are not so defined by the manufacturer and provide minimum requirements for all UPS systems. Batteries for the UPS shall be flooded types wherever possible. Isolation transformers shall be used on all UPS systems above 10 kVA.
All components of the UPS shall be removable via front access.
UPS shall be modular to help design growth. Maintainability shall be stressed in the design. The design shall allow modular replacement for repair as much as possible.
The design should be such that failure of any one module will not cause a complete UPS malfunction.
UPS nameplates shall contain the following information as a minimum: Supplier’s name, UPS model number and serial number, kVA rating, nominal input and output voltages, and manufacturing date.
6.2 Definition of Terms
UPS Definitions:
• AC LOAD PROTECTION — Devices to allow one of several loads to be isolated for fault clearance or maintenance.
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• BATTERY BANK — a group of cells/monoblocs used to provide the required reserve power to the inverters while there is no AC input to the rectifiers. The battery bank should be sized to provide the reserve for a minimum of 5 minutes
(typical design is a minimum of 15 minutes) at full load, but may be designed for much longer reserve times, at an admittedly higher cost (for critical Network circuits in COs [and possibly in some RT/Prem sites], the desired reserve time is at least 4 hours, but a minimum of 2 hours is required). For sites where the UPS serves high heat-density loads, long battery reserve times are untenable since the served equipment will fail without the air-conditioning provided by enginealternator or commercial AC). (Note that at least in Tier III and Tier IV Data
Center designs, there are multiple strings of batteries, and because the equipment is typically at least dual fed from more than one UPS, any one UPS is typically not loaded to greater than 40%, so the actual reserve time is often at least 3 times the designed reserve time.)
• BATTERY DISCONNECTS — a means to open leads between the UPS and the battery bank. This device should safely open both the + and - leads, as most systems are not grounded on either battery lead. The device must be rated for the voltage and current of the battery bank. For DC battery strings having a voltage greater than 250, disconnects are also usually placed mid-string to minimize technician risk during maintenance.
• BYPASS — a source of AC power (commercial AC or engine-alternator backup) that will replace the inverter output. This source can be internal or external.
• HARD/MAINTENANCE BYPASS — an external source of AC that will allow shutdown of the UPS for maintenance and provide AC for distribution while the
UPS power electronics components are not energized.
• DOUBLE-CONVERSION — This type of unit always converts AC power to DC, and then inverts it back to AC, providing truly uninterruptible and protected AC power to the load.
• FLYWHEEL — Some UPS systems (commonly known as rotary UPS systems) are equipped with a heavy flywheel (instead of battery backup) that provides
10-15 seconds of backup by storing rotational energy.
• INVERTER — Unit that converts DC to the necessary AC voltage required by the distribution system, normally 120/240 V single-phase, or 120/208 or 277/480 V three-phase.
• LINE-INTERACTIVE — This UPS unit normally passes a surge-protected commercial AC source through to the load, but switches to battery backup
(through the inverter) in less than 4 milliseconds when the source is lost, or the quality of the AC waveform is poor.
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• OFF-LINE — This UPS unit normally passes a surge-protected commercial AC source through to the load, but switches to battery backup (through the inverter) in less than 4 milliseconds when the source is lost.
• ON-LINE — (see the definition for double-conversion.)
• RECTIFIERS — change AC to DC to power inverters and float the battery banks.
• ROTARY UPS — a UPS consisting of an electric motor coupled through a clutch to an alternator (sometimes incorrectly called a generator), and including a heavy flywheel to keep the alternator spinning for a short time period when commercial AC power is lost to the motor.
• STATIC TRANSFER SWITCH — a very-fast acting (typically less than 4 ms) automatic transfer switch that transfers a UPS (or -48 VDC powered inverter) from AC source to the DC backup or vice-versa.
• STATIC UPS — a traditional UPS consisting of power electronic components (in rectifiers and inverters), and DC backup (usually batteries).
• SUPER™/ULTRA™ CAPACITORS — may be used in a static UPS to provide very short duration (almost always 2 minutes or less, and typically 10-30 seconds) DC backup to feed the inverters.
• TRANSFER SWITCH — A means of transferring the distribution system from the inverter's output to an alternate source, usually commercial power, or a source that can be transferred to a standby generator.
6.3 Technical Requirements
Outlets served from UPS shall be labeled as to source.
CAUTION
High voltage may be present on both the AC and DC sides of an UPS. AC or DC voltages may be as high as approximately 545VDC and 480VAC.
AC wiring must be sized to meet manufacturers’ specifications. Rigid conduit must be used in areas where activity could jeopardize the integrity of the system.
Four hundred Hz systems may require the use of line regulators to provide a match of impedance between the load and the UPS.
Breakers feeding CenturyLink ™ equipment must be coordinated to ensure proper isolation of feeders due to faults/overloads. The input and output main circuit breakers shall be equipped with a factory-installed shunt-trip capability for UPS larger than 10 kVA that will be installed in sites/rooms/areas requiring EPO shutoff of these UPS per the requirements of NEC ® Article 645 (EPO should be avoided wherever possible).
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DC wiring must be sized to meet manufacturers’ specifications for loop loss between the battery and the rectifier or inverter. The voltage drop must meet National Electric
Code (NEC ® ) requirements. When the batteries are separate from the power electronics components of the UPS, the DC leads are usually run on cable racks or trays and should have RHW, RHH or XHHW type insulation. Conduit may be used if both positive and negative leads are run in the same conduit. Conduit may be used only if other means are not available due to space requirements.
The operating temperature of all AC and DC wiring in UPS equipment will not exceed
20 degrees F higher than the ambient room temperature or 46 degrees C (115 degrees F) whichever is higher.
Electrically operated disconnect devices (aka EPO switches) are required in some computer room installations by Code. EPO switches/buttons should be guarded and preferably be pull-type rather than push-type.
The neutral lead of UPS systems must be grounded at one point only because it is a separately derived source when equipped with any transformer. A dedicated transformer and switchgear are normally used to provide bypass power. The neutral must be grounded at the secondary side of this transformer. The ground lead must not be switched. Grounding of computer areas served by UPS must be in accordance with the UPS manufacturers’ specifications and the requirements defined in Technical
Publication 77355, Chapter 11 (the neutral and ACEG grounding of the output of the
UPS in covered in Sections 4.2 and 5.5 of that same Pub). Ground bonds between the
UPS plant and the metallic structures shall consist of electrical conductors specifically provided for grounding purposes. Incidental paths through framework, cable rack, building steel, etc., shall not be used for grounding purposes. Daisy chaining between frames is not permitted. The doors of the UPS enclosures shall be equipped with grounding strap connections for static electricity control.
The major power electronics components (and monobloc VRLA batteries) of UPS larger than 40 kVA shall be housed in freestanding, "dead front" vertical enclosures with a maximum height of 7 feet. The enclosures may be mounted on heavy-duty casters with leveling screw jacks. The enclosures shall be equipped with "piano-hinged" doors or equivalent. These doors shall be equipped with locking mechanisms to prevent the doors from opening. All sheet metal used in the enclosures shall be 16 gauge or better.
All joints and seams shall be welded. Cable entry shall be through either the top or the bottom of the cabinet.
Forced air-cooling and/or ventilation are normally required. Blower motors shall be equipped with sealed roller (ball) bearings. Each enclosure with a blower for UPS larger than 40 kVA shall have a redundant blower. A failure of a blower unit shall generate an alarm. All air inlet and exhaust openings shall be protected with expanded metal guards.
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Chapter 6
Uninterruptible Power Supplies (UPS)
UPS designed to serve non-linear (non-sinusoidal, or high harmonic) loads shall have an output voltage THD of less than 20%. No single harmonic shall have an output distortion of less than 10% under any or all of the following conditions: up to 100% non-linear load; up to 100% load current THD; and/or a load current crest factor up to
3.0.
The UPS shall have built-in protection against under voltage, overcurrent, and over voltage on both the input and output.
The UPS shall conform to NTA, Telcordia ® (Bellcore) TR-TSY-000757, Issue 1, Generic
Requirements for Uninterruptible Power Systems . The UPS shall also be Listed.
Wherever possible and feasible, flooded batteries specifically designed for high discharge rate applications will be used with UPS, rather than VRLA batteries. When
VRLA batteries are used, those designed specifically for high discharge rates (or general purpose batteries designed for many types of discharge rates) shall be used.
6.4 Alarming and Control
The UPS shall produce alarms as described herein and in Chapter 8.
Internal alarms and monitoring devices shall be built into the UPS to identify failed modules. Monitoring of VRLA batteries with a permanent monitor (based on the items discussed in sections 8.2.3 and 8.6.3) is desirable, especially if the UPS serves critical loads and only has a single string. Some UPS have the battery monitoring built into them, but for those that don’t have this, external monitors are available. Wireless communication by UPS battery monitoring devices is not allowed in Central Offices and major long-haul transport sites (wired connections are always encouraged).
If the UPS utilizes a microprocessor and software for control, detection of a UPS unit failure shall be built into the software. It is desirable that microprocessor-based units be equipped with an IP port for html and/or SNMP communication, or at least serial data communication through an RS-232 port. Microprocessor driven UPS alarm/control will be either fully redundant, or capable of self-diagnostic and isolation in case of a microprocessor failure. This isolation will remove the microprocessor control from the system, provide a dry contact alarm, and revert to conventional operation.
All UPS shall be equipped with dry contacts for connection to an alarm system; these contacts will provide indication of UPS unit failure and operating status.
Battery backup (separate from the batteries used for the primary backup of the loads fed from the inverter) may be provided within the UPS to maintain power to the internal clock or save microprocessor settings, in case of failure of the power source. If such memory battery backup is provided, a low battery voltage alarm shall be provided allowing sufficient time to permit battery replacement on a non-emergency basis.
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Chapter 7
Standby Engine-Alternators
CONTENTS
Chapter and Section
7.
Page
Standby Engine-Alternators ...................................................................................... 7-1
7.1 General .............................................................................................................. 7-1
7.2 Site AC Power Systems .................................................................................. 7-3
7.3 Sizing and Ratings .......................................................................................... 7-4
7.4 Alternator Technical Requirements ............................................................. 7-5
7.5 Control Cabinet and Transfer System Requirements ................................ 7-6
7.6 Additional Engine Requirements ............................................................... 7-11
7.7 Voltage and Frequency Regulation ............................................................ 7-12
7.8 Additional Paralleling Requirements ........................................................ 7-14
7.9 Alarms and Shutdowns ................................................................................ 7-15
7.10 Fuel and Lubrication Systems ..................................................................... 7-18
7.11 Exhaust System Requirements .................................................................... 7-24
7.12 Starting Systems ............................................................................................ 7-25
7.13 Cold Starting Aids ........................................................................................ 7-25
7.14 Acoustic Noise ............................................................................................... 7-25
7.15 Cooling System .............................................................................................. 7-27
7.16 Safety ............................................................................................................... 7-28
7.17 Hazardous Voltages ..................................................................................... 7-29
7.18 Portable Engines and Trailers ..................................................................... 7-30
7.19 Portable Engine Connections ...................................................................... 7-30
Figures
7-1 30-Ampere Cable Hardwired to Single-Phase Engine-Alternator ..................... 7-34
7-2 30-Ampere Cable to Single-Phase Engine-Alternator Receptacle ..................... 7-35
7-3 30-Ampere NEMA ® L14-30P Locking Connector Pin Configuration ............... 7-35
7-4 100-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connector, Cable
Hardwired to Single-Phase Engine-Alternator .................................................... 7-36
7-5 100-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connectors, Cable to Single-Phase Engine-Alternator Receptacle ..................................................... 7-36
7-6 100-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connector, Cable
Hardwired to Three-Phase or Single/Three-Phase Engine-Alternator ............ 7-37
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CONTENTS (Continued)
Figures (continued) Page
7-7 100-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connectors, Cable to Three-Phase or Single/Three-Phase Engine-Alternator Receptacle ............. 7-37
7-8 100/200-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve Receptacle
Front-View Pin Configuration ................................................................................ 7-38
7-9 100-Ampere IEC 60309 Orange Plastic-Sleeve 4-Pin Connector, Cable
Hardwired to Single-Phase Engine-Alternator .................................................... 7-38
7-10 100-Ampere IEC 60309 Orange Plastic-Sleeve 4-Pin Connectors, Cable to Single-Phase Engine-Alternator Receptacle ..................................................... 7-39
7-11 IEC 60309 Orange Plastic-Sleeve 100 Amp Receptacle Pin Configuration ....... 7-39
7-12 200-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connector, Cable
Hardwired to Single-Phase Engine-Alternator .................................................... 7-40
7-13 200-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connectors, Cable to Single-Phase Engine-Alternator Receptacle ..................................................... 7-40
7-14 200-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connector, Cable
Hardwired to Three-Phase or Single/Three-Phase Engine-Alternator ............ 7-41
7-15 200-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connectors, Cable to Three-Phase or Single/Three-Phase Engine-Alternator Receptacle ............. 7-41
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7. Standby Engine-Alternators
Chapter 7
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7.1 General
This unit contains requirements for all standby AC systems and equipment including engine-alternators with automatic transfer equipment to be deployed in all
CenturyLink ™ facilities. Standby AC power plants provide long term backup for essential AC loads, as defined in Chapter 1 of this publication.
Terminology commonly used for AC power plants includes emergency, reserve, auxiliary, and standby. Standby (as opposed to "Emergency") is used in this document in conformance with the definitions of Article 701 "Legally Required Standby Systems" and Article 702 "Optional Standby Systems" of the National Electric Code (NEC ® ); as well as the definitions given in NFPA ® 37 and NFPA ® 110. The use of the term emergency should be avoided because true emergency engines and their associated AC systems have many additional maintenance and wiring requirements in the NEC.
The grounding system of a separately derived source (the minority of enginealternators) shall be per Tech Pub 77355 Chapter 4, and NEC ® Articles 250.30 and NEC ®
250.20B. Grounding for most engines (those that aren’t separately derived sources) shall conform to Sections 4.8-4.10 of Tech Pub 77355, and Article 250 of the NEC.
All engine-alternators must conform to local code and should be coordinated with the local, state, or federal agency having jurisdiction.
Air dryers and/or compressors must not be installed in the engine rooms due to the static electricity and heat generated. In fact, engines should be in their own room or outdoor enclosure (per NFPA ® 76) for fire safety reasons, and in a separate room from the AC switchgear for reliability reasons.
CenturyLink ™ doesn’t require n+1 for engines or transfer gear, although paralleled engines in an n+1 configuration should be considered for the most important facilities.
In some cases of load growth, if engine horsepower is sufficient to support a larger alternator, it may be less expensive to replace just the alternator rather than the entire engine-alternator set. This might also be the case if the alternator fails.
Operating documentation (including control programming and prints/drawings) must be provided with each engine-alternator and transfer system. The documentation should include how to start or shut down the engine; how to back out of a transfer operation; how to manually transfer the system, and how to transfer the load when load shedding. If these can be shortened to a sheet or two for each operation, these sheets should be laminated and posted on the transfer and engine control cabinets.
Single-line diagrams for a site must be updated (and preferably laminated) by the electrical contractor whenever an engine or transfer system is added or replaced.
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All systems and equipment to be deployed in telecommunication sites shall satisfy the relevant space and environment requirements of Telcordia ® (Bellcore) GR-63-CORE.
Major spatial (building space) requirements for standby AC plants are shown as follows:
• The clear ceiling height required for installation of an engine in a room shall not be less than 12 feet 6 inches. This means the minimum height from the floor surface to the bottom of the lowest building structural. Coordination may be necessary to ensure that the standby AC plant installation will not interfere with cabling, air ducts, or other building systems.
• The equipment weight, averaged over any 20 by 20 foot floor area, should not exceed an absolute limit of 140 pounds per square foot (140 lb/ft 2 ) for equipment, supporting structures, cabling and lights, unless the floor has been certified by a building engineer to be able to support more weight. Special building structural considerations may exist due to the load concentration and dynamic loads associated with the engine/alternators. Professional Engineers contracted by the CenturyLink ™ Real Estate Department can determine this, plus any earthquake bracing that must be done for the engine installation at the specific site location. Outdoor engine enclosures should be placed on a pad designed to the engine-alternator manufacturer’s specifications to withstand exposure, meet the local Codes, and support the weight and vibration. Unless otherwise specified, the minimum generator pad will be constructed of at least 6” thick reinforced (typically reinforced with 10 AWG wire mesh on a 6x6” grid and
#8 rebar) concrete. The concrete strength shall be at least 4000 psi (a 6 sack mixture). The engine enclosure should be centered on the level pad (with a minimum of 3’ on each side and 2’ on each end) and anchored at all 4 corners.
• All connections from the engine/alternator (e.g. exhaust, fuel lines, coolant lines, electrical, etc.) shall be made with a flexible section for control of vibration. For outdoor engine enclosures, lines should enter through the pad on the bottom, or through another method that limits their exposure to the outdoors and to vibration damage.
• The environmental requirements in Telcordia ® GR-63 and GR-1089 address temperature, humidity, heat dissipation, fire resistance, earthquake, office vibration, air borne contaminants, grounding, acoustical noise, illumination, electromagnetic compatibility, and electrostatic discharge. Environmental test methods are included in these NEBS ™ documents, and they may be used for evaluating equipment compliance with these requirements.
CenturyLink ™ requires a factory representative to go to the job site for the initial start up of an engine-alternator.
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The design engineering and installation of power systems for all sites served by an engine-alternator should conform to the requirements of Occupational Safety and
Health Administration (OSHA) and all applicable local health and safety codes. All power systems and equipment shall be designed and constructed to comply with applicable requirements of the NEC ® and with applicable local electrical and building codes. When special requirements are necessary, they will be furnished by the
CenturyLink ™ Engineer. The standby AC plant, as installed, shall also conform to the requirements of NFPA ® 37 (Standard for the Installation and Use of Stationary
Combustion Engines and Gas Turbines); NFPA ® 110 (Standard for Emergency and
Standby Power Systems); and the “Flammable and Combustible Liquids Code" (NFPA ®
30) or the “Liquified Petroleum Gas Code” (NFPA ® 58); including the placement of bollards as required by NFPA ® 30 or NFPA ® 58 and local Codes and AHJs, depending on the location of above-ground tanks and outdoor engine enclosures.
The documentation for standby AC plants shall be provided in a clear, concise, and organized manner per CenturyLink ™ requirements. The information shall include all the equipment building environmental requirements.
Engine-alternators should not be re-used in another site if they are over 30 years old.
Before they are re-used they should be looked at by a qualified diesel mechanic, either a
CenturyLink ™ employee, or an outside engine-alternator vendor.
7.2 Site AC Power Systems
A typical AC power system for a site equipped with a standby engine-alternator consists of the following:
• Commercial AC Service Entrance
• Standby AC System
— Engine-alternator
— Transfer System
• Building AC Distribution System
— Essential AC
— Non-Essential (may not exist in smaller buildings)
The main building AC disconnect should preferably be outside the engine room but relatively nearby.
For CenturyLink ™ sites other than buildings, AC requirements are defined in Chapter
11.
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Commercial AC is the normal energy source for most CenturyLink ™ sites. A prolonged commercial power fail requires backup in the form of standby AC for telecom services and essential building services. The standby AC system consists of one or more engine driven alternator(s), transfer system(s), electrical and mechanical controls, fuel storage and supply system(s), combustion air intake and exhaust systems, engine starting system(s), and cooling systems appropriate to the type of equipment employed.
The size and type of standby AC system is determined by the combined building and equipment loads that require essential AC service. Telecommunications equipment may represent only a portion of the total load. The alternator kW should generally be sized between 125-333% of the essential load (see the next section for further detail).
7.3 Sizing and Ratings
Standby engine-alternator power plants are power-limited sources that can be overloaded by simultaneous starting of connected loads.
In order to avoid transient overloads or oversizing of the engine, large motors (such as those found in chillers and other HVAC) should be on lead-lag control, and any VFDs should have soft-start. In addition, it might be necessary to add sequenced starting of rectification, although this need is rare because modern rectifiers have current walk-in.
Standby engines shall be designed and configured for reliable starting and continuous operation at full load within a range of operating conditions specified for CenturyLink ™ sites. Generally, the engines should be sized (based on the criteria below) between 125 and 333 % of the existing peak load on the site (peak load will occur on battery recharge in the summer). The more growth in load expected at the site over the next 10 years, the more the sizing would be towards the 333 percent. When an engine is sized at greater than 333 percent of the existing peak (which normally shouldn’t be done except in cases of extreme expected load growth), diesel engines will need to be permanently or periodically load-banked to prevent wet-stacking (if the site can be served by a portable load bank, that load banking for these oversized engines as compared to the existing load should be done at least annually for a minimum of 4 hours; but if the site is inaccessible to a portable load bank, a permanent load bank may need to be installed).
The system capacity specified shall be while operating under the following conditions:
• Alternator output at the kW rating specified in the paragraph below.
• Operating at the site specified altitude
• Operating at the specified engine room ambient temperature
• Maximum back pressure from the exhaust piping system
• Maximum drop of radiator air handling system
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• Maximum pressure of fuel supply system imposed on the engine fuel pump.
• De-rating for sites with high total harmonic content (voltage THD > 15%).
The kW (kiloWatt) rating of all engines shall be based on the Continuous Duty Rating at an 80% power factor. For small applications (under 30 kW where the power factor of the engine-alternator is 1.0), the engine-alternator must be capable of providing a peak load of 125% of the kW rating of the unit.
AC standby power systems shall provide outputs within Range A limits specified by
ANSI document C84.1, "Voltage Ratings (60 Hz) for Electrical Power Systems and
Equipment”, and provide one of the preferred systems voltages per Table 1 of C84.1.
7.4 Alternator Technical Requirements
The alternator’s design and performance shall comply with National Electrical
Manufacturers Association (NEMA ® ) MG 1, Part 22. The windings shall be
"tropicalized" (i.e. designed to minimize effects of fungi and moisture). Alternators shall also meet the following requirements:
• Insulation for the rotor and stator shall be Class H per NEMA ® MG 1, Section
1.65, and shall be designed to last at least 20 yrs or 10,000 operational hours.
Design full load temperature rise shall not exceed the continuous duty values in
NEMA ® MG 1, Section 22.40
• The engine-alternator shall be capable of continuously delivering the output kW specified by the CenturyLink ™ Engineer for environmental ambient temperatures from –34 degrees C to 52 degrees C (-30 to 125 °F) and at the altitude where the engine-alternator is installed. The manufacturer shall supply de-rating charts in
1000 foot increments (de-rating may be estimated in the absence of a chart as
3.5% per 1000 feet for liquid-cooled engines and 5% for air-cooled engines). This requirement shall be met at any power factor from 80% leading or lagging to unity, at any voltage within the limits of ±10% of rated voltage, and at a frequency of 60 Hz ±3 Hz.
• The alternator shall conform to the provisions of NEMA ® MG 1, Sections 22.41 and 22.45, "Maximum Momentary Overloads," and "Short Circuit Requirements", respectively. Ground fault protection is required for sets with output voltages
≥ 480 VAC and/or output currents of 1000 Amperes or greater.
• The rotors (alternator and exciter) shall be in both mechanical and electrical balance at all speeds up to 125% of rated speed.
• The alternator bearings shall be the antifriction type. The bearings, shaft, and housings shall be so designed as to prevent leaks onto the machine parts or windings. Each bearing shall be sealed for life.
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• The deviation factor of the alternator open circuit terminal voltage shall not exceed 6%. The deviation factor is determined in accordance IEEE Standard 115,
“Test Procedures for Synchronous Machines”.
• The balanced line-to-line open circuit voltage TIF (telephone influence factor) shall not exceed 50. The line-to-line open circuit low frequency modulation is not to exceed 0.5 Volts peak-to-peak, in the frequency range of 5 to 30 Hz. The total open circuit harmonic content of any line-to-line or line-to-neutral voltage shall not exceed 3% rms, with no single harmonic exceeding 1.5%.
• Alternator leads shall terminate on the line side of the breaker. A means will be provided to prevent connectors from turning when mounted on breaker studs.
• Each engine-alternator set will be mounted on vibration isolators, either internal or external to the sets' skid base, as determined by the CenturyLink ™ Engineer.
• Exciters (if used) shall be brushless, using a rotating rectifier bridge circuit.
—
Exciter field current shall be automatically controlled by the voltage regulator. This regulator shall also provide under frequency protection.
• The output circuit breaker shall be equipped with adjustable instantaneous trips, long time trip elements (thermal trips), and a shunt trip circuit.
—
When an on-set breaker is required, the breaker assembly shall provide contact closure for OVERCURRENT audible, visual, and remote alarms.
Lockout contacts should be provided and interfaced with the control circuit to prevent starting of the engine before the breaker is reset.
—
The engine-alternator breaker trip settings shall protect the alternator from damage due to AC system faults, and avoid nuisance tripping.
• AC grounding will be in accordance with CenturyLink ™ Technical Publication
77355 and the NEC ® . The only acceptable method of grounding the neutral of a set producing 480 VAC power or less is to solidly connect it to the neutral of the commercial power at the house service entrance.
7.5 Control Cabinet and Transfer System Requirements
To minimize potential loose connections or trouble spots in the control circuitry, all interconnections of control circuitry wiring shall be stranded wire with crimp connectors and ring terminals securely fastened to terminating points with a machine screw (preferred). Only one termination shall be provided per screw.
The only gauges that aren’t part of the controller that may be on a stationary engine are oil pressure, temperature, tachometer (if applicable), and fuel pressure non-electronic gauges. These gauges must be capable of remote connection to the control cabinet.
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A stationary engine-alternator must have a control cabinet. The control cabinet shall be
NEMA ® 1 (as a minimum for indoor applications; and may need to be NEMA ® 3 or higher and weatherproof for outdoor applications), with a hinged door. Contents of the controller shall be solid state. The solid state controller shall not be physically mounted on the engine-alternator unless there is vibration isolation (in which case it’s metallic enclosure shall be bonded to the set’s chassis with a braided strap or stranded wire).
The engine-alternator set and/or control cabinet shall include the following:
• Gauges and Meters (may be part of a digital display instead of analog):
1.
Oil Pressure
2.
Coolant Temperature
3.
Output Ammeter and Voltmeter (with selection for each phase)
4.
Running Time Meter
5.
Frequency Meter
• Manual Selector Switch/Button(s) with positions for:
1.
RUN or MANUAL operation
2.
STOP or OFF
3.
REMOTE or AUTOMATIC operation
• Others:
1.
Remote, 2-Wire control start-stop terminals
2.
Manual reset Field Circuit Breaker
3.
Indicator lamp(s) for the alarm conditions causing an automatic engine shut down.
4.
A manual alarm-reset switch shall be provided (either on the engine or remotely) to clear the indicators and reset the system to allow engine restart after shutdown.
5.
Manual reset Exciter Field Circuit Breaker (where applicable).
6.
Emergency STOP switch.
7.
Dry alarm contacts for each failure condition.
8.
If not adjustable via digital display, potentiometers shall be provided to adjust:
— Voltage (5%)
— Frequency (2%)
The remote control cabinet shall meet the requirements of this document. All connections between the remote control cabinet and the set cabinet will be run in conduit. These leads may be run along with the alarm leads.
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The cabinet shall be front access via a hinged door that will latch (outdoor cabinets must be lockable unless they are behind a locked gate). All switches, lamps, gauges, and meters shall be mounted on the door. All electrical wiring shall be routed and secured to prevent connection deterioration due to movement and to allow access to the cabinet interior.
For floor mounted cabinets, leveling screws, wedges, or shims shall be part of the usable cabinet to level and plumb the cabinet and to compensate for variations in floor flatness. In addition, there shall be four holes provided in the corners at the bottom of the cabinet that will allow 5 /
8
-inch anchor bolts to secure the cabinet to the floor. The cabinet shall have a kick plate extending a minimum of 4-½ inches from the floor.
All Automatic Transfer Systems shall be LISTED to Underwriters Laboratory (UL ® )
1008 or 1066 (restricted and certified are not acceptable), and meet the requirements of
NEMA ® ICS 10, Part 1 Standard, and ANSI C37.16. The transfer system should be sized to the main entrance facility whenever possible.
The transfer system itself shall be able to withstand 100% of its closing ratings.
Each automatic transfer system can be either an electrical or solenoid-operated mechanism. The transfer system should be either circuit breakers or a switch. If breakers are used, these breakers may be used as the ground fault current protection device (when that is required for larger systems and/or higher voltages). Where permitted by local Code, the commercial breaker may also serve as the main service breaker. External shunt trips with engine start inhibit may be provided if required by local fire codes.
Circuit breakers shall be of the thermal-magnetic type, rated for the fault current, and must be Listed. Contacts shall not be able to be held closed during an overcurrent condition by holding the lever in the closed position. They shall be trip-free type. The
AC circuit breakers shall be clearly marked as AC breakers (not DC). AC breakers shall generate an alarm signal when they either are in the tripped state or turned off.
The transfer system and its devices shall meet all requirements of the applicable UL ® and ANSI standards and be rated for fault current. Ferrous materials shall not be used for current-carrying parts.
All transfer systems shall be equipped with plug-in elements, or a maintenance bypass isolation switch to facilitate maintenance and replacement (such as the inspection and replacement of main arcing contacts) without creating an extensive power outage.
Automatic transfer systems can be either equipped with a load disconnect delay option
(preferred) or closed transition switching (not recommended for Network sites). The disconnect delay option shall be set for a 3-7 second delay.
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The manufacturer shall supply interconnection information for connecting the enginealternator with an Automatic Transfer System. A manufacturer’s representative shall review all installed new transfer systems to ensure they are properly installed and working.
There shall be a single standby engine-alternator test switch mounted on the AC switch gear. This test switch will simulate a Commercial AC failure to the standby enginealternator and all transfer systems. Operating this Test switch will cause all of the standby engine-alternators to start, and all transfer systems that operate when there is an actual AC failure to transfer. Restoring this test switch will cause the standby engines and transfer systems to proceed with their normal timing to return to
Commercial AC and engine shut down.
For all automatic transfer, the system shall be capable of the following:
1.
Recognize the occurrence of a power failure.
2.
Open the commercial power source.
3.
Start the engine-alternator set.
4.
Close the alternator circuit breaker and/or transfer to the alternator
(availability indicated by a light).
5.
Automatically control loading of the emergency bus.
6.
Recognize the return of commercial power (indicated by a light).
7.
Transfer all loads from the standby power source to the commercial power source (only if the commercial AC load has been restored for 30 minutes).
8.
Shut down the engine-alternator.
There shall be a time delay for engine start (at least 5 seconds), a time delay on retransfer to permit polyphase motor stop, a time delay on shutdown to permit engine cool down (minimum 5 minutes unloaded), and a time delay before transfer to engine to permit warm-up, polyphase motor stop or sequential loading. There shall be a minimum run time (at least 30 minutes loaded for engines smaller than 300 kW, and at least 45 minutes loaded for engines larger than that). All of the above times will be per engine manufacturer’s specification.
For automatic paralleling of multiple engines, the system shall be capable of performing the following operations:
1.
Recognize the occurrence of a power failure.
2.
Open the commercial power source.
3.
Initiate the Start signal to all engines simultaneously.
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4.
The first engine to reach proper voltage and frequency closes its on-set breaker initiating closure of the engine transfer breaker powering the static loads;
5.
As additional engine-alternators are paralleled to the essential bus, the Load
Management Controller connects these loads on a priority basis.
6.
Recognize the return of commercial power.
7.
Transfer all loads from the standby power source to the commercial power source after the Holdover Timer has operated (the holdover timer should ensure that commercial AC is back and stable for at least 15 minutes).
8.
Shut down the engine-alternator.
There shall be engine-starting contacts that will allow each unit to be started independently.
For automatic paralleling of the engines to the commercial grid system, the ATS shall be capable of performing the following operations:
1.
Initiate the Start signal to engine;
2.
Bring the engine up to speed;
3.
Synchronize and parallel it with the utility;
4.
Gradually transfer all loads from the commercial source to the standby source;
5.
Open the commercial power source;
6.
Upon completion the controls shall synchronize and parallel it with the utility;
7.
Then it shall gradually reduce the load on the standby source to zero;
8.
Then it shall open the standby source connection;
9.
Shut down the engine-alternator.
Note: Utility company permission must be obtained to allow paralleling to the commercial grid with the CenturyLink ™ engine/alternator. Special protection mechanisms may be required by the utility to ensure that the engine-alternator will not export power onto their grid when they want it de-energized for maintenance. The paralleling of the two power sources increases the short circuit current magnitude on the building distribution system. The engineer must consider this when specifying the short circuit interrupting rate of the distribution system protective devices.
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The standby AC plant shall be equipped with load management features. Both manual and automatic control capabilities shall be provided for sequential operation of the served load. The system shall provide suitable time delays to prevent failure of the standby plant, too quick of a disconnect from commercial AC, and/or too quick of a standby engine-alternator start in response to transient conditions.
The system shall be equipped with a test switch to facilitate simulation of a power fail.
It shall also be equipped with a manually controlled retransfer override. The system shall have indicating lights to indicate the source feeding the load (all transfer switches and engine control panels with indicating lights should have a lamp test feature).
Each automatic transfer system shall include a control panel. The transfer system should preferably be outside the engine room (but relatively nearby). An isolation plug in the wiring harness shall be provided to disconnect all circuits between the control panel and the main transfer panel.
Full-phase voltage sensing must be provided. Full phase protection shall also be provided. Three-phase relays may be field adjustable, close-differential type, with
92-95% pickup, and 82-85% dropout. Relays are to be connected across the commercial
AC voltage input line side of the transfer system.
Independent voltage and frequency sensing of the commercial source must be factory preset to initiate transition to standby at 90% voltage and 58 Hz.
Overvoltage and over-frequency sensing of the commercial source (to initiate disconnect from commercial, and startup and transfer to engine) is highly desirable, and should typically be adjustable from 110-120% of nominal voltage and 62-64 Hz.
Exercise timers may be provided. If provided, they must be adjustable for monthly (or
1 or 2 weeks in special circumstances, when requested) operation.
Synchronization for paralleling (whether to the bus or the grid) must occur within 20°.
The neutral shall not switch except on sets where the output voltage exceeds 600 VAC.
The neutral and ground shall not be bonded at the transfer system, although they may be bonded at a very close panel in small sites.
Meters may be either analog or digital.
The overcurrent protection device can be either a fuse or a circuit breaker placed in the ungrounded supply lead.
All components must be marked on both the schematic drawings and in the cabinets.
New transfer systems must be microprocessor or PLC-controlled. Microprocessorcontrolled is preferred with a non-proprietary interface.
Transfer systems should be installed indoors whenever possible.
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For nominal 208 V systems of greater than 2000 A, or nominal 480 V systems of greater than 800 A; upon loss of a single-phase (for more than 10 sec) from either commercial or engine source, the transfer system should lock out the respective source and issue an alarm. The transfer system may be set up to automatically allow reconnection if the lost phase returns for 10 sec or more; or it may be set up to require manual intervention.
This single-phase lockout prevention is allowable for smaller systems too. The system may be powered from the engine start-control batteries or from an AC inverter source.
Single-phase lockout is not required for sites with single-phase protection built into the chiller motors’ input circuitry.
7.6 Additional Engine Requirements
Engines must be "In-Line" or "V", water cooled, and mounted on a common steel subbase. The engine must ship with required accessories (except items subject to shipment damage). All parts shall be new. Engines should have replaceable cylinder liners.
All engine-moving parts must be maintainable. Any "lifetime" - permanently lubricated parts must be easily replaceable and 100% warranteed for material and labor for a minimum of 7 years from the date of installation.
7.7 Voltage and Frequency Regulation
The voltage regulator shall be of the solid state design and shall not be frequencysensitive between frequencies of 55 to 67 Hz. The regulator shall sense all phases.
On engine-alternator sets equipped for parallel operation, the regulator circuit shall have adjustable cross current compensation. The voltage droops due to the cross current compensation circuitry shall be adjustable from 0 to 5% of the set's rated voltage and shall be factory set at 3.5 to 4%.
The voltage regulator shall be furnished with an adjusting rheostat (or be adjustable via a digital controller) that allows the alternator terminal voltage to be adjusted ±10% of its normal value. Means for voltage adjustment shall be furnished at the control cabinet.
With the voltage regulator operating, the cross current compensation shorted out, and the thermal effect constant, the regulator shall control the terminal voltage at any load from 0-100%, and from 0.8 leading or lagging to 1.0 power factor. This terminal voltage shall be within 2% of nominal when the no load speed is as much as 3 Hz above 60 Hz.
With the voltage regulator operating, the regulator shall hold the alternator output terminal voltage constant within 2% over an environmental ambient temperature range from --30 degrees F to 125 degrees F, with a speed change of ±5%, based on the following conditions:
• The cross current compensation is shorted out.
• The load power factor is between 80% leading or lagging and unity.
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• The engine has stabilized at its operating speed.
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• The governor is adjusted for any droop between 0 and 5%.
• The ambient temperature remains within a 30° F band after 5 min of operation.
Each alternator, exciter, and voltage regulator should have under frequency and over voltage protection, including for shutdown and/or coast down conditions.
When load on an engine-alternator is increased in 25% steps from 0-25%, 25-50%, 50-
75%, and 75-100%, the output voltage should recover to within 0.5% rms of the previous voltage within one (1) second after reaching the new load.
When the full-rated kVA load is rejected in one step, the transient surge voltage shall not exceed 20% of the rated voltage and shall recover to within 1% of the new steadystate voltage within two (2) seconds.
Either a hydraulic or an electronic governor that meets the following requirements can be used. Isochronous type governors are preferred, with the engine-alternator set manufacturer to specify the type used.
• The governing system shall be capable of providing frequency vs. load regulation characteristics from isochronous to 5% droop.
• There shall be no sustained periodic variations in alternator output frequency under any conditions, including abrupt load changes.
At any constant load from no load to full load, the maximum frequency ripple for the
AC output shall be 0.15 Hz (¼%) at any frequency between 57 and 63 Hz and at any load from no load to full load. This requirement is intended to apply at steady state conditions including stable temperature within the governing system. Frequency variations within the 0.15 Hz range shall be random (aperiodic).
Frequency drift due to changes in governing system temperature shall not exceed ±0.15
Hz for steady state operation at any load from no load to full load.
Note: "Steady State", for the purposes of this requirement is defined as operating at constant real (kW) load for a minimum of 5 minutes after full speed is attained at start up, or, for a minimum of 2 minutes after the disappearance of transients in output voltage and frequency due to a load change.
After stabilizing at steady full load conditions, the engine-alternator set shall return to the same output frequency ±0.15 Hz when load is repeatedly added or removed. This requirement shall be met for isochronous and droop operation, where applicable.
The output frequency shall be adjustable over the range of 57 to 63 Hz from the system control cabinet. External droop adjustment shall be provided at the governor or, where droop adjustment is via electrical means, by means of a potentiometer located within the engine control cabinets.
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For both increasing and decreasing loads, the change of alternator output frequency with load shall be within ¼% of true linear response with the governor set for any droop between 0 to 4%.
The response of the engine-alternator set to sudden changes in load shall meet the following criteria:
• For any sudden quarter-load change from no load to full load (increasing or decreasing the load) the frequency shall recover to and stay within the 0.15 Hz band within one second.
• For any sudden full load change (full load to no load), the frequency shall recover to and stay within 0.15 Hz band within 2.5 seconds.
• For any sudden quarter-load change from no load to full load (increasing or decreasing the load) the frequency shall depart from the steady state value by no more than 2% of the steady state value.
• For any sudden full load to no load change, the frequency shall depart from the steady state value by no more than 5% of the steady state value.
• For all of the above, the frequency shall stabilize at the steady state value after no more than one overshoot and no more than one undershoot.
Hydraulic governor mechanisms, where used, shall be designed to employ the same oil used in the engine.
7.8 Additional Paralleling Requirements
For engine-alternator sets equipped for parallel operation, the voltage regulator and governor circuitry shall be designed to allow droop compensation type paralleling.
Standby engine-alternator sets equipped for automatic paralleling shall also be provided with means for manual synchronization (e.g., phase lamps, sync scopes, etc.).
For paralleling applications, the engine-alternator breaker will be of the size and type to ensure protection of the engine-alternator in case of out-of-phase paralleling.
Each alternator set equipped for parallel operation shall have suitable characteristics to permit it to be paralleled with another unit or units specified by the CenturyLink ™
Engineer. Each set shall be capable of operating in parallel with the set(s) so specified at any load from no load to full load, at any power factor from 1.0 to 0.8 lagging, while meeting the following requirements:
• Circulating current shall not exceed 10% of the combined full load current of all sets in parallel.
• The transfer of power between sets shall not exceed 2% of the rating of one set, and such transfer shall not be cyclic.
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• The division of real load between sets shall be proportional to the set capacity.
For automatic paralleling, the system shall also be capable of paralleling the alternators and sending signals to automatically close successive load group circuit breakers as each associated alternator is brought on-line (or the load can be transferred all at once, if not too large, when all sets are paralleled);
Recognize the non-operation of any alternator(s) and open the designated load circuit breakers to shed/disconnect those loads to maintain system operation if there is not sufficient capacity to support all of the loads. If an existing site without n+1 redundancy in a paralleled engine-alternator system serves a 911 PSAP, or hosts a 911 selective router, and it does not have an automatic load-shedding control system, the site must have a posted manual load shedding plan.
7.9 Alarms and Shutdowns
Standby AC plants must be capable of extended operation without human intervention, since there should be remote surveillance of alarms. The standby AC plants covered by these requirements shall provide alarm interfaces with maintenance and operation systems in accordance with requirements in this publication.
An alarm termination strip shall be provided for all the engine alarms. The engine installer shall run the alarms from the engine to the terminal strip. The terminal strip(s) should normally be in an EAT (Engine Alarm Termination) box located in the power room or engine room. The installer will be required to label the engine alarms and analog monitoring points on the terminal strip(s). Engine alarms and analog monitoring points are covered in this chapter and in Chapter 8. The alarms and analog points are run from the EAT box to the PSMC by a CenturyLink-hired subcontractor familiar with PSMC installation and programming.
Normal shutdown of standby AC plants operating under manual control shall be accomplished by depressing a "STOP" or "OFF" switch located on the plant control panel. It shall be placed in a convenient location, readily accessible and clearly marked.
A momentary contact push button type switch designated "EMERGENCY STOP" shall be provided on each control panel or cabinet. When this switch is actuated, the set shall shut down and an alarm indication shall be given. The "EMERGENCY STOP" switch function shall also be capable of being duplicated by a switch located as required by local code (generally outside the engine room or enclosure door). The button/switch shall be in a housing, or otherwise protected, to prevent accidental operation.
There must be a manual shutdown device mounted on the engine. Operating it will:
• Shut down the engine;
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• Close a solenoid-operated valve in the fuel line (unless there is an anti-siphon valve as an alternative to the solenoid valve in non day tank sites, or if the fuel tank is below the engine);
• Activate alarm circuits; and
• Disable the set's starting circuits
Operating conditions to be monitored for standby AC plants include those listed below.
Where an engine-alternator set employs additional features or support systems essential to proper operation of the plant, additional monitoring and/or alarms may be required. Visual alarm and status indication shall be provided by colored lamps mounted directly on the local and, where present, remote control cabinet. Provisions shall also be made for transmitting alarm signals per the alarm requirements in this publication.
• The local control cabinet will be equipped with meters or gauges (or these values shall be displayable on the digital controller), with minimum accuracy as indicated below in parentheses, providing the following outputs:
1.
Alternator Output (alternator output meter shall be duplicated on the remote control cabinet, where equipped);
—
Amperes (3.0%)
—
Volts (3.0%) (Engine and Commercial)
—
Frequency (1.0%)
—
Kilowatts (2.0%)
—
Lubricating Oil Pressure (5%)
—
Fuel Pressure (5%)
—
Lubricating Oil Temperature (5%) (over 900 kW)
—
Engine Temperature (3%)
—
Hours of Operation (0.1 hour)
—
Tachometer
2.
Engine Start Battery voltage (always operational, not just during run)
• The control cabinet and/or transfer system should be equipped with step-down current and voltage transformers to meet the monitoring needs of the Power
System Monitor Controller at the site (these are most often only in the transfer system on the load side, or in a subsequent load side cabinet).
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An alarm indication shall be given and the plant controls shall shut down affected standby engine-alternator sets if one or more of the conditions listed below exist. For each of the conditions listed in this section, the engine-alternator set shall shut down and require a manual reset after the problem has been cleared in order to restart the set.
• Low Engine Oil Pressure— operates if the oil pressure falls below the safe value recommended by the manufacturer
• Engine Over Crank — operates if the engine does not come up to a threshold speed within 10 seconds after three cranking attempts
• Engine Over Speed — operates when engine rpm exceeds 108-125% (most engines are capable of at least 125% overspeed without damage) of normal operating speed (the overspeed sensor is often factory present between 116-125% of rated speed, but when allowed, and user-adjustable, it may be set lower – between 108 and 110% – as a safety margin). (Turbines operate at higher speeds than internal combustion engines, and where used, must have tighter overspeed controls: a maximum overspeed setting of 115% is all that is allowed.)
• Over/Under Voltage or Under Frequency — operates if the alternator voltage exceeds normal range by ± 15-18% and/or the frequency deviation is greater than
3 cycles for 5 cycles (the engine should shut down on an inverse time delay basis)
• Over Current — operates if the alternator circuit breaker trips open
• Reverse Power — (required only for engine-alternator sets equipped for parallel operation, which may include paralleling with the commercial power) operates if the engine-alternator receives reverse power in excess of the threshold value specified by the manufacturer
• Differential Fault — (required only for engine-alternator sets rated 800 kW or larger and when the engine output breaker is less than 50% of the transfer system breaker) on sets so equipped, operates if the differential fault relays are energized due to differential fault current
• Ground Fault — (required only for engines with output voltages ≥ 480 VAC and/or sets with rated output current of 1000 Amperes or greater) on sets so equipped, operates if the ground fault protection device is activated. (Ground fault detection devices may be set to cause tripping of the alternator output breaker up to 1200 Amps, but it is more typical to set them between 100 and 400
A. They should not be set too low, or nuisance tripping will occur. A study by a licensed electrical P.E. may be needed to determine the proper setting for the particular building and AC motors it contains that will cause the least amount of equipment damage while still avoiding nuisance tripping.)
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• Control Breaker or Fuse — operates if a circuit breaker or fuse providing power to essential engine-alternator set control functions operates
• High Coolant Temperature — operates if the temperature of the coolant, measured on the engine side of the set mounted thermostat, exceeds recommended coolant temperature by 15% (sensing arrangements shall be such that a shutdown signal will be issued if loss of coolant occurs)
An alarm indication shall also be given if one or more of the following conditions exist.
These conditions indicate impending problems, which may result in plant shutdown or other impairment if corrective action is not taken.
• Charger Failure — an Alarm shall be issued if the charger(s) floating the start/control batteries fail (or have high or low voltage)
• Fuel System Trouble — for plants equipped with auxiliary fuel pumping systems and/or day tanks, an alarm shall be issued if the fuel level in the day tank is above or below the normal range
• Preliminary High Coolant Temperature — an alarm may be issued if coolant temperature in a liquid cooled diesel engine rises to within 10 degrees F of the
"High Coolant Temperature" shutdown point (although this alarm may be available, it might not be wired past the EAT box, depending on the spare points available on the PSMC)
• Low Coolant Temperature and/or Heater Failure — an alarm shall be issued if the heating element fails or if coolant temperature drops to a level that may impair starting reliability
• Visual Alarm Codes — Visual alarm and status indications are defined in
Chapter 1 except as noted.
Note: A red indicator on a circuit breaker indicates closed and is not an alarmed condition — per the NEC.
7.10 Fuel and Lubrication Systems
The rate of fuel supply to the engine's injection system shall be as required to prevent stalling, overspeed, or over temperature under any steady state or transient loading conditions within the engine-alternator's rating, and when operating within the environmental limits (temperature, altitude, and humidity) of Telcordia ® GR-63.
Manufacturers shall provide fuel consumption charts for their systems operating at full,
¾, and ½ loads.
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Acceptable fuels that may be considered are diesel, natural gas, LP gas (a mixture of propane and butane, where propane should predominate, especially at lower temperature sites), and gasoline (gasoline should be avoided for permanent engines due to long-term storage difficulties, shorter life, and increased maintenance of gasoline engines). Natural gas engines should be backed up by a propane source.
Note: In special environments governed by special governmental rules (National
Forest, National Parks, wilderness, etc.) the fuel used will be based on regulatory requirements.
Diesel engines shall be capable of using No. 2-D, or winter blend (#1 and #2 diesel combination) fuel per ASTM Specification D-975. Where regulatory bodies require or seek to require the use of biodiesel blends, CenturyLink ™ should seek exemptions for its permanently-installed engine-alternator sets. Biodiesel blends do not store well, even with biocide and pour-point depressant additives. Where the local regulatory rules/laws require the use of biodiesel blends in telecommunications backup enginealternators in spite of the best efforts of CenturyLink, periodic fuel filtering/cleansing will be required. This can be done by a contractor or CenturyLink employee on a routine (every 1-4 months for biodiesel blends that contain more than 5% biodiesel, and every 4-12 months for biodiesel blends that contain 5% or less biodiesel); or especially with higher quantity biodiesel blends (above 5%), a permanent on-site pumping filtering system (possibly equipped with a periodic timer) may be considered.
Install the fuel tank as near as possible to the engine without violating Code (for example, fuel tanks generally cannot be placed within 500 feet of a public water supply; sensitive/protected ground water transition/recharge receptor zone; or registered/ known underground drinking, irrigation, or other beneficial water well). Because the fuel pump influences tank location, the manufacturer shall provide fuel pump lift data.
The use of double wall tanks with a cavity leak detection system is preferred (doublewalled tanks are required for all direct-buried tanks). All single-walled tanks must have a containment structure — vault, curb, etc. All double-wall tanks, and vaults must be able to contain an overfill of at least 10%.
Above-ground storage tanks (ASTs), which include vaulted tanks (even if the vault is below grade), are generally preferred over direct-buried tanks (USTs), and fiberglass tanks are preferred when direct-buried due to regulatory paperwork. Depending on soil conditions and local regulations, direct-buried steel tanks may require cathodic protection (active or passive). CenturyLink ™ has a corrosion engineer who may be consulted, in addition to or as an alternative to outsourcing the work to a qualified P.E.
More information on cathodic protection of tanks can be found in IEC BS EN 13636.
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Fuel tanks should be sized going forward at a minimum of 48 hours of reserve based on full engine load (sites hosting 911 selective routers are required to have 72 hours of combined battery and engine reserve at the actual peak fuel run rate with a 90% full tank). Depending on how hard the site is to access in the winter, or if the site is in a hurricane-prone area, tanks with much greater reserve may be decided upon by the
Power Engineer. The fuel consumption is given by the engine manufacturer. However, if it can’t be found, it can be estimated as 0.07 gal/kW/hr at full load for diesel fuel and
0.1 gal/kW/hr for gasoline, natural gas, and LPG (propane) engines at sizes 50 kW and larger. For smaller sizes, estimate use at 0.1 gal/kW/hr for diesel and 0.14 gal/kW/hr for gasoline, natural gas and LPG. Generally, diesel and gasoline tanks shouldn’t be filled above 90% (95% being an absolute maximum); and LPG tanks shouldn’t usually be filled above 80% (85% being an absolute maximum).
A day tank is a fuel transfer tank used when the engine’s fuel pump doesn’t have the lift to draw fuel from the supply tank. Day tank pumps (and all other electric fuel tank pumps) may be DC-driven from the engine start/control batteries, or driven from the essential AC bus (pumps driven from essential AC may be necessary when the “lift” is extreme).
DAY TANKS SHALL BE AVOIDED WHENEVER POSSIBLE by use of a high-lift fuel pump when the required fuel lift is between 6-18 feet or the tank is more than 50’ away.
Note that if the lift is less than that, no day tank or high-lift pump is required: the standard on-set engine pump can do the job. Day tanks are generally required when the lift is greater than 18’ (or the equivalent due to piping length, bends and other things that add to backpressure, thus increasing the effective lift). They are also generally required when the tank is above the engine by more than a few feet. Use of a day tank in these instances reduces the pressure (thus lengthening life) on the input seal of the on-set fuel pump.
If the use of a day tank is unavoidable, it shall incorporate both a containment device and a leak detection alarm. In addition, it should be equipped with a high fuel level and a low fuel level alarm. It should be equipped with a vent that is routed outside of the building. It should be sized to provide a minimum of 1 hour engine run at full load.
Base fuel tanks under the engine are allowed, but when used, if they elevate common engine service points (such as oil and coolant drain and add points, filters, etc.) to more than 6’ off the floor or ground, a catwalk must be provided in CenturyLink ™ Local
Network sites.
When a day tank or high lift fuel pump is not used, and the tank is not above the engine, the return line should extend at least halfway down into the main tank (so that it is normally submersed) to prevent air getting into the fuel system due to backflow.
The return point in the tank should be spatially far away from the feed line pickup.
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Fuel tanks and exhaust emissions shall be monitored in accordance with EPA, State,
Local, and CenturyLink ™ requirements. Contact the local CenturyLink ™ Environmental
Consultant and/or CSPEC Engineer and/or Real Estate Engineer for approved fuel tank monitoring systems and locally required inspection schedules. At a minimum, fuel tanks must have a low fuel alarm.
All direct-buried tanks and any above-ground or vaulted underground tanks where the total site fuel storage equals or exceeds 1320 gallons must also have an overfill alarm, and a monitoring system capable of at least monthly leak detection tests, including the interstitial space between the two tank walls. Fuel tank monitors shall be equipped with a dialup modem and a working phone line (some sites where phone service is inaccessible may be exempt from this requirement).
Fuel delivery/return systems shall meet all national and local codes, including Listing of appropriate components. When rigid piping is used for diesel, it must be doublewalled (double-walled is always required for buried pipe) or black iron (per ASTM spec
A53), and a minimum of 6 inches of flexible piping, or Aeroquip™ or Stratoflex™ hose in sealed containment shall be placed between the engine and the supply and return lines. Natural gas or LPG piping may also be galvanized steel or a Listed and NFPA ®
30 or NFPA ® 58 compliant synthetic material (fuel piping should meet ASME B31, and non-metallic fuel pipe must be Listed to UL ® 971). Natural gas pipe must be coated/ wrapped, of the minimum size required by the local gas company, be able to carry at least 150% of the full-rated fuel flow of the engine, and buried a minimum of 24” when underground. It is recommended that outdoor fuel lines be buried or protected when in locations susceptible to vandalism/damage, or when they are a tripping hazard
(including on rooftops). A sight window/glass shall be provided in the feed fuel line.
In some jurisdictions, fire marshals or insurance requirements may require a valve (in the feed line – this is also true for return lines that are under pressure, such as when the fuel tank is above the engine) that closes if there is a fire in the engine room/enclosure.
This valve contains a meltable link that closes the valve when the temperature reaches approximately 195 degrees in the room/enclosure. CenturyLink ™ requires installation of these valves going forward for all diesel fuel supply lines in buildings except when there is a belly tank. Natural gas feeds require a manual shut-off valve at the engine.
All new standby diesel engine-alternators shall be equipped with an engine oil cooler.
Grounding of fuel tanks shall conform to CenturyLink ™ Technical Publication 77355,
Chapter 4. In addition, copper and galvanized piping shall not be used in fuel systems because of the impurities they may introduce into the fuel injectors.
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A solenoid-operated valve (powered from the engine start/control batteries; although it may be powered from the essential AC bus on sites with day tanks) in the fuel line feed shall be provided and connected to the emergency stop switch (closes when the switch/ button is pressed or the wiring is open). This solenoid-operated valve may be supplanted by an anti-siphon valve if there is no day tank; and it is not required in sites with the tank below the engine. It is preferable that this solenoid-operated valve be at the highest point in the line between the main tank (it may even be located on top of the tank) and the engine, or at least at a point above the engine fuel pump if possible. If the placement is outdoors, the solenoid valve should be enclosed in a rain-resistant opaque enclosure. For sites where the main tank is located above the engine pump, the solenoid valve must be located between the main tank and the first point of entrance into the engine room/enclosure (it may be placed right after it enters the room/enclosure). For sites without a day tank, the solenoid valve is not needed if an anti-siphon valve is installed as close as possible to the point where the fuel line leaves the main tank (note however that the anti-siphon valve does cause a bit of an addition of back pressure). When main fuel tanks are located above the engine or day tank they serve they shall have an anti-siphon valve in the feed line at the point they enter the engine room. It is desirable to have a bypass with a normally closed manual ball valve around anti-siphon and solenoid valves for diesel engines to allow for quick temporary function of the engine if the anti-siphon and/or solenoid valve(s) fail.
The primary and secondary fuel filters and strainers shall be of the replaceable element type and of sufficient capacity to permit a minimum of 200 hours of continuous operation without requiring service.
Note: This requirement must be met when operating with fuels containing total organic and inorganic particulate matter (i.e., 1 micron or larger) of up to 5 milligrams per 100 cm 3 of fuel. For example, if the engine filtration system(s) removes 100% of the particles 1 micron or larger, the filter or combination of filters shall be sized to trap and hold approximately one pound of particulate matter for every 2000 gallons of fuel circulated through the filters.
Diesel fuel systems may be equipped with water separators.
The fuel control system shall not require lubrication, adjustment, or other maintenance more often than every 500 operating hours.
A manually-operated, DC electrical or mechanical, permanently-mounted priming pump shall be incorporated in the on-set fuel system. The priming system shall be capable of priming the complete on-set fuel system, starting with drained fuel lines to the supply tank and a drained on set fuel system, in 1 minute or less.
When a high lift fuel pump is used, it shall be capable of delivering at least 120% of the set's fuel consumption rate when the set is operating at full-rated load and the suction lift (including flow losses in pipe and fittings) is 15 vertical feet of diesel fuel.
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The fuel system may consist of two supply and return loops (day tanks are required to have two supply lines [each with its own pump] from the main tank for reliability):
• Fuel from the main or day tank flows through a fuel strainer, a gear or beltdriven fuel pump, and possibly into a fuel cup (the fuel cup is on engines with a high lift pump). A return line provides a path for fuel not consumed to return to the tank. This return line shall normally be free from traps and/or valves (a check valve may be used where the tank and/or a significant portion of the return line is above the engine), and shall be at least as large as the supply line.
A return pump may be required in rare instances for long distance runs or vertical lift (for tanks above engines by more than a few feet) in order to overcome backpressure.
• The second loop runs from the fuel cup (on those engines with a fuel cup) to the engine's fuel metering/injection system (usually filtered and boosted by a highpressure fuel transfer pump) with unburned fuel returning to the fuel cup (or to the day or main tank in the absence of a high lift pump).
Filter elements in the engine lubrication system shall be adequately sized to permit a minimum of 168 hours of continuous operation without replacement of the elements.
The lubricating oil capacity of the set shall also be adequately sized to enable unattended operation for a minimum of 168 hours.
Positive lubrication shall be provided for all moving parts in the engine and accessory drive. The lubricating oil pump shall be gear-driven from the engine.
Lubricating oil filtration shall be of the full-flow type. The lubricating oil filter shall have a built-in bypass arranged to permit oil to bypass the filter if the filter element becomes clogged. Lubricating oil filters shall be of the replaceable element type.
If the lubricating system is designed to require priming after the system is drained for any reason, a manually operated pump shall be provided. This pump shall be permanently mounted on the engine-alternator set.
Lubricating oil vapors shall not be vented within the building unless the engine room only ventilates to the outside. All lubricating oil vapors from the engine should be recycled or consumed within the engine. The crank case breather tube shall be routed to a discharge damper duct of the radiator, or in some other manner that avoids oil residue buildup on an on-set radiator fan.
A lube oil pressure switch/gauge equipped with pressure sensors shall be provided to operate appropriate electrical contacts to shut down the engine if lubricating oil pressure falls below a safe level.
When engine oil sumps (pans) are not easily accessible, they shall be equipped with a drainpipe, valve, etc., to facilitate changing of the oil.
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The engine exhaust manifold channels exhaust gases from each cylinder to an exhaust outlet. The manifold shall afford a minimum of backpressure and turbulence to the engine cylinders and valves. The two primary types of manifolds are the dry air-cooled and the water jacket water-cooled. Air-cooled with a standard steel flange is preferred.
Exhaust pipes must comply with applicable codes. Minimum requirements follow:
• Pipes shall be wrought iron or steel and strong enough to withstand the service.
• Pipes must not be supported by the engine or silencer.
• Pipes must use vibration proof flexible connectors.
• Pipes must have a clearance of at least 9 inches from combustible materials and terminate outside the building.
• Pipes in an engine room or walk-in enclosure (not applicable to external engine enclosures that aren’t walk-in) must be guarded and/or insulated to prevent burn injuries to personnel (and possibly excessive heat) in an engine room. The guards or insulation is not required to extend above 7 feet high. Insulation used solely to prevent heat buildup is at the discretion of the designer of the system.
• All connections shall be bolted flanges with gaskets, or welded. No automotive type exhaust pipe clamps are permitted.
• The outlet of the exhaust pipe should be a 90 degree horizontal bend, designed for minimum back pressure, with the end of the pipe cut at a 45 degree angle, scarfed, with expanded metal over the open end. For cases where the outlet must be vertical (to meet air quality rules, or prevent backflow of the exhaust into the intake, etc.), caps and or bird screens should be used to prevent intrusion of water or debris, but hinged rain caps are not permitted due to their propensity to rust shut (unless they are made of aluminum or stainless steel).
• Exhaust pipes shall not terminate within 10’ of a fuel tank vent or fill cap.
A piece of flexible, bellows-type exhaust pipe must be used between the engine exhaust connection and the exhaust piping system.
Provide Exhaust silencer(s) for engines, sized per manufacturer recommendation and/ or as a result of an engineering acoustical noise analysis to meet local requirements, and be engineered for a site-specific sound level. Place the silencer close as practical to the engine to avoid unwanted carbon deposits. If the exhaust stack rises more than 20 feet, and/or ends vertically, a water drain plug may be considered at the muffler/silencer.
Exhaust must extend above the building whenever possible, and not be placed near building fresh air intakes. Exhaust must meet local/state/federal laws/requirements.
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The battery shall be sized to permit a minimum of five (5) cranking attempts of 30 seconds at the design low engine room temperature specified by CenturyLink ™
(40 degrees F). After the third cranking attempt, no more attempts to start the engine should be made, and the control cabinet should issue an alarm labeled "overcrank".
The start and control batteries shall be Ni-Cd or Lead Acid type. The batteries shall be covered with protection while working on the engine-alternator set (if they are right next to the set). The start and control batteries shall be marked with the installation date. Where applicable, the battery stand is to be a heavy earthquake zone installation.
Engine driven alternators/generators shall not be used on a going forward basis for start and control battery charging.
Engines rated 600 kW and larger should have redundant starter motors and batteries.
The engine start batteries shall be floated with a regulated (filtered) charger. A start battery charger may be mounted either in the control cabinet or mounted on a wall near the start battery stand. The charger shall have the following:
• output capacity of 2 Amperes minimum
• output Voltage and Ampere meters/display
• adjustable output voltage
• internally protected output leads
• high and low voltage alarms
• charger fail alarm
It is desirable that the charger have temperature compensation to avoid overcharging.
7.13 Cold Starting Aids
All water-cooled diesel engine-alternator sets shall be provided with thermostaticallycontrolled heaters or a heat exchange system, designed to maintain jacket water temperatures not lower than 90 degrees F (per NFPA ® 110) and not higher than 120 degrees F. Because traditional electric heating elements wear out, it is desirable to equip the cooling system with manual valves (preferably ball valves, but never valves or hoses with quick disconnects) on either side of the heater (as close to the engine block as possible) so that the entire cooling system doesn’t have to be drained to effect an element replacement or heater hose replacement.
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For warmer climates, or externally heated engine rooms, it is permissible on dual element heating systems to only connect for half the Wattage output in order to lengthen the life of the block heater system. For engine-alternator sizes in excess of 750 kW, it is desirable that the heating system have some sort of circulation pump, since natural thermo-siphoning may not provide heat to all areas of the water jacket on these large engines.
Engine rooms (and their ventilation systems for use during engine run) should be designed for a max temperature (while the engine is running) approximately 15 °F above the ASHRAE maximum summer outside ambient temperature for that location.
For all engine-alternator sets to be installed where outdoor ambient temperatures will fall below 40 degrees F, provisions shall be made to keep the indoor engine room temperature at a minimum of 40 degrees F, or have a battery heater pad that maintains the batteries at that temperature. It is preferred to have the engine start and/or control batteries at an indoor temperature (when the engine is not running) between 50 degrees and 90 degrees F (see NFPA ® 110). The temperature shall be allowed to go up to 120 degrees F if the engine start/control batteries are Ni-Cd.
7.14 Acoustic Noise
Sound levels within the building housing the standby plant and outdoor sound levels resulting from operation of this equipment shall meet the requirements specified by
OSHA, Telcordia ® GR-63, and local codes as specified.
Where the engine-alternator set is equipped with a sound attenuating enclosure, the enclosure shall be designed to allow adequate cooling of the engine-alternator set.
Sound-attenuating enclosures, where employed, shall provide hinged doors or latched panels to allow access for normal maintenance and repair operations, including:
• removal and replacement of fuel and lubricating filters
• replacement or cleaning of air filters
• performance of all other manufacturer-specified normal maintenance operations
Where the engine-alternator set is equipped with a sound- attenuating enclosure; it is desirable that the enclosure cooling requirements be met without booster fans or other accessory devices.
Note: The supplier must consider widely different climates in CenturyLink ™ . Some locations will require booster fans or other accessory devices.
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Acoustical materials, such as acoustically absorbent liners, shall be non-capillary, nonhygroscopic, free from perceptible odors, and must maintain their acoustic attenuating properties under the conditions of temperature, mechanical vibration, and exposure to petroleum products to which they may be subjected under normal operation.
Elastomeric material used in sealing the acoustic enclosure must remain flexible and resist cracking in the environment they are exposed to in normal use.
7.15 Cooling System
The cooling system for the engine-alternator (water-cooled is preferred to air-cooled for all engine-alternators 10 kW and larger, with the only exception being for documented space reasons) shall have sufficient cooling capacity to ensure continuous operation at full load at ambient temperatures up to 50 degrees C (122 degrees F) at the site altitude.
Engines may have a switch that shuts down the engine when the radiator fan fails.
Some installations require the radiator and fan mounted separately from the enginealternator. This is known as a remote radiator, and the following requirements apply:
• When water flow is produced by the engine driven water pump, total piping pressure drop shall not exceed the engine manufacturer’s recommendation. If water flow is assisted by an auxiliary pump, piping pressure drop must be matched to pump capacity at desired water flow, per manufacturer specs.
• Remote radiators are designed for installations where no external airflow restrictions occur. If the remote radiator ventilates a room, has any ducting, or its airflow is opposed by prevailing winds, the cooling capacity is reduced.
• Areas with below freezing temperatures’ will require consideration to protect against ice formation that can block air flow or damage fan blades.
• A remote radiator fan requires an electric motor compatible with the standby power source. The voltage, frequency, and horsepower of the required motor must be specified. The fan can be direct-drive or belt drive. If belts are used, multiple belts must be employed to ensure reliability. An indicator lamp must be on the Engine Control Panel, indicating proper operation of the fan. The fan motor shall be powered from the engine-alternator it serves.
• Remote radiators shall be grounded to the existing driven ground system if it can be located. If the existing driven ground system is not available a lead from the remote radiator shall be run outdoors to a point close to the OPGP. At that point, it may enter the building and tie to the OPGP. In addition, the external radiator lines will be bonded to the site’s internal ground system where they enter the building.
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• Heat exchangers shall be utilized when the engine manufacturer’s specified maximum head pressures are exceeded. If a heat exchanger is required, an auxiliary pump shall be used in the system. The pump shall be powered from the engine-alternator it serves.
• The remote radiator fan shall be rated as "Quiet" with a maximum noise level of
81 dBa measured at twenty-five (25) feet.
When the radiator is mounted on the same sub-base as the engine-alternator, the cooling fan shall be mechanically driven from the engine. The fan shall be of the pusher type (that is, the cooling air shall be blown through the radiator). Where the fan is a belt-driven, a redundant belt shall be provided, so that if one belt breaks, the remaining belt(s) shall be capable of driving the fan continuously. These set-mounted radiator fans shall also be equipped with a shroud / duct flange for safety reasons.
The set-mounted cooling systems as described above shall be capable of operating with total fan head pressure equal to or greater than 0.5 inch of water.
If air intake has ductwork, a flexible radiator section, (rubber or flame retardant canvas type is preferred), shall be utilized to connect the radiator with the ductwork.
Silicone type radiator hoses are required for use in all 3D-condo buildings. Elsewhere silicone, or teflon, or high-pressure thick rubber hose is most desirable on the hoses that connect to the block heater, but is recommended elsewhere in the cooling system too.
Outdoor enclosures shall provide access to service the coolant level. A sight glass and low coolant level alarm shall be provided for all outdoor engines 300 kW and larger.
Radiator sight glasses shall also be provided for indoor engines larger than 800 kW.
Louvers on the combustion / radiator cooling / exhaust air openings to engine rooms or enclosures are not absolutely required, nor are filters on the air inlets (filters are a site-by-site decision based on the amount of dust, dirt, and other pollutants that might be drawn in). However, when louvers are used, they must be powered closed so that they spring open (using a mechanical spring) upon loss of power to the louver motors.
Louver motors should be powered off the engine start-control batteries or off an
Essential AC bus, and are activated by the engine start-stop control signals. The design of the louver system shall satisfy the engine air requirements of the particular engine with a maximum design back pressure of ½ inch of water column.
7.16 Safety
The engine-alternator set shall be designed and constructed so that personnel hazards are minimized. Component parts shall be suitably arranged and labeled and/or guards shall be employed to minimize the possibility of accidental contact with hazardous voltages, rotating parts, excessively sharp edges, and/or high temperature surfaces per
OSHA CFR29 Part 1910 and NEC Article 445.14.
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Materials and components employed in the standby AC system shall meet the requirements for fire resistance as stated in Telcordia ® GR-63.
Exposed equipment surfaces below the 7 foot level where temperatures will rise to greater than 46 degrees C (115 degrees F) shall be marked with warning labels (the warning label does not have to attach to the surface, but can be nearby in a highly visible location – for engine rooms, a warning on the door may be sufficient). Insulation and/or ventilated guards shall be provided to protect the operator from coming into accidental contact with the high-temperature external surfaces of diesel engine exhaust system parts and piping; plus any other components with surface temperatures higher than 54 degrees C (130 degrees F) when the engine is not running (a general high temperature warning label on an engine room door is sufficient warning for when the engine is running). Temperature guarding requirements do not apply to outdoor engine enclosures that are not walk-in type (the enclosure provides the personnel protection); nor do they apply more than 7 feet above the ground.
The appropriate NFPA ® 704 hazard diamond sign shall be provided for fuel tanks, and any room door behind which a fuel tank may be located. In addition, the house service panel (HSP, also known as the service entrance) must have a sign near it (per NEC ®
Article 702.7) noting the location of the on-site engine-alternator.
Engine room / fuel tank areas shall be labeled to prohibit smoking (within 50’ for propane, in addition to “flammable” and “propane” labels for LPG tanks) nearby per national and local Codes. Eye and ear protection requirements (as well as an auto-start warning) shall be labeled at engine room doors (see OSHA CFR29, Part 1910).
Suitable guards shall be provided for all rotating parts to which the operator might be exposed to, including all fans, blowers, and any other rotating parts of alternators.
• Guards shall be of substantial construction; removable but securely fastened in place and of such design and arrangement that any part of the operators' body cannot project through, over, around or underneath the guard.
• All set screws, projecting bolts, keys, or keyways shall either be suitably guarded or of a safety type without hazardous projections or sharp edges.
• All running gears and sprockets exposed to personnel contact shall be enclosed or be provided with band guards around the face of the gear or sprocket. Side flanges on the band guard shall extend inward beyond the root of gear teeth.
7.17 Hazardous Voltages
Voltages at or above 150 Volts DC or 50 Volts AC rms shall be enclosed or guarded to prevent accidental personnel contact. Warning labels shall also be provided and conspicuously displayed so that they are visible with guards in place or removed.
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7.18 Portable Engines and Trailers
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The portable engine-alternator (the AC engine-alternator is sometimes incorrectly referred to as a portable generator or genset, since a generator has a DC output) shall meet all requirements of the previous sub-sections of this Chapter, except that grounding conductors need only be sized to meet the NEC ® requirements).
Although the ratio of portable engines to sites is a local decision, new ones must be equipped as described in this document. Examples of items to be considered when determining the ratio of generator sets to sites are:
• Area covered (including typical area climate)
• Voltage and phase configurations of sites to be covered (single/three-phase combo gensets are available and recommended for areas that have sites with differing voltage and phase configurations)
• Number of high priority sites
• Power company restoration history
• Tolerable down time duration
For liquid-cooled engines, a coolant heater shall be provided that can be plugged into a typical 120 V outlet. The battery charger will also be connectable to a 120 VAC outlet.
Portables larger than 15 kW shall be mounted on a multiple axle-type trailer that meets all Department of Transportation and local requirements.
• The trailer shall have a locking tool box. Among the items in this toolbox, there will be four rubber wheel chocks, and any adapter cords that are necessary to connect to the sites that could be realistically served by this portable.
• The trailer will be equipped with surge brakes, towing lights (lights, wiring harness, and connector), and an adjustable towing hitch.
• The trailer and portable will have a minimum 100 gallon fuel tank and gauge (or equivalent for LPG tanks).
• Permanently mounted generators or alternators must be grounded to the vehicle chassis they are mounted on. However, the neutral and ground should not be bonded together at the engine since that connection already exists at the AC meter, and we do not switch the neutral at the transfer system.
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All 15 and 20 A convenience outlets on the vehicle/trailers must be equipped with
GFCI protection. These outlets are intended to provide power for test equipment and tools, instead of powering the telecommunications equipment. Single-phase 30 A receptacles (see Figure 7-2) on engines 15 kW and smaller, are required to have GFCI protection, per NEC ® Article 590.6A3. Any other outlets or cordsets, including hardwired 30 A cordsets (see Figure 7-1) and 30 A receptacles on engines larger than 15 kW, should not have GFCI protection in order to avoid nuisance tripping.
7.19 Portable Engine Connections
Standardization of portable engine connection hardware meets the need for a quick positive response during extended power failures. This section presents the standards for new equipment and enables retrofitting of existing equipment/sites.
Portable engine sets shall be grounded according to Tech Pub 77355 and the NEC.
Sites equipped with a permanent engine are generally not equipped with portable receptacles. However, for large/important locations, it may be wise to have a tap box to allow faster connection of a large rented portable. As an alternative to a tap box, for sites that need up to 400 A per pole, single-pole connectors are available. Sites served by portables where the manual transfer switch size exceeds 200 A shall either have a tap box, or single-pole connectors (when the transfer switch size does not exceed 400 A).
When tap boxes are used, they should be connected such that two sources cannot be tied together simultaneously. This may be done with a manual transfer switch, interlocked breakers, etc.
There are many variations of portables in use by CenturyLink. Primarily, units capable of producing a rated power output from 3.5 to 75 kW will be addressed in this section.
Although almost all RT powering is 120/240 Volt single-phase, some of these sites may be served by engines capable of single or three-phase operation. These engines are sometimes also used with three-phase sites (typically 120/208 Volt three-phase wye, but could be 240 V three-phase delta). For conformity, some of the 100 ampere connectors and all of the 200 Ampere connectors have been designed to accommodate these types of engines. The 100 and 200 Ampere inlets have 4 pins, but only 3 of the pins are used on single-phase sites when a UL ® 1686 C1 Style 1 compliant metallic-case is used where the ACEG "green-wire ground" is connected to the metallic case of the plugs and receptacles (all 4 pins are used on plastic-sleeve 100 Ampere IEC 60309 orange inlets designed for single-phase service).
The plugs, receptacles and cable sets illustrated in the Figures in this section have been standardized for use in CenturyLink. The local Power Maintenance Engineer should be consulted before gauge (AWG) changes are made to the power cables specified in this document.
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The Ampere rating of the plug chosen (see the Figures) will depend on the ultimate load expected at a given site (this load is to be computed by the Design Engineer, who should then specify the Ampere rating of the AC service and portable genset plug).
All hardware, including power panels, cabling, and devices shall be Listed by a
Nationally-Recognized Testing Laboratory (NRTL). Installations shall conform to the
NEC ® and local electrical codes.
Van or truck mounted engine-alternators presently in service capable of producing
120/240 Volt single-phase AC are generally 3.5-13 kW in rating. They shall be equipped with at least a two pole 30-Ampere breaker. (The 30-Ampere plug is only actually rated to carry about 6 kW of 240 V power. The breaker will protect the cabling, engine, and plugs from having their ratings exceeded.) As an option, a cable may either be permanently attached to the engine-alternator terminal block as, or the alternator terminal block may be wired to a NEMA ® WD-6 L14-30R locking receptacle.
The DLC housing or power pedestal shall be equipped with an L14-30P inlet. The typical 25-30 foot cable run between the engine and the site inlet must use four #10
AWG conductors in a Type W cable.
Van, truck, or trailer mounted engines presently in service capable of producing 100 A of 120/240 V single-phase AC, 120/208 V 3-phase wye, or 240 V 3-phase delta power shall be equipped with at least a 2-pole 100 A breaker for single-phase sets, or a 3-phase
100 A breaker for 3-phase or three/single-phase sets. (The 100 Ampere plugs are actually rated to carry only about 20 kW of nominal 240 V single-phase power, 30 kW of nominal 208 V 3-phase wye power, or 35 kW of 240 V 3-phase delta power. The breaker will protect the cabling, engine, and plugs from having their ratings exceeded.)
As an option, there may be a cable permanently attached to the engine-alternator terminal block, or the alternator terminal block may be wired to a either an IEC 60309 plastic-sleeve receptacle or a Style 1 (ACEG attached to the metal housing of the receptacle) UL ® 1686 C1 4-pin pin-and sleeve device with a metallic housing on the connector. The site housing or power pedestal shall be equipped with either an IEC
60309 inlet plug, or a Style 1 UL ® 1686 C1 pin and sleeve reverse-service (the reverseservice connectors ensure that “hot” power is not on an exposed pin) inlet plug.. For single-phase sites, pin 3 may be pulled on the building/site side of a 100 or 200 Amp inlet, as shown in the drawings . The typical 25-30 foot cable is made up of four or five, number 2 gauge conductors in a Type W, UL ® sheath. Engines that are capable of threephase operation will have five (5) conductors in their cables.
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In some cases, the power requirements of a site served by a portable engine will exceed
100 A. Trailer mounted engine-alternators capable of producing 200 A of 120/240 V single-phase AC shall be equipped with a 2-pole 200 A breaker for single-phase sets, or a three-phase 200 Ampere breaker for 3-phase or 3-phase/single-phase sets. (The 200 A plugs are actually rated to carry about 40 kW of 240 V single-phase power, 70 kW of 240
V delta 3-phase power, or 60 kW of 208 V 3-phase wye power. The breaker will protect the cabling, engine, and plugs from having their ratings exceeded.)
200 A connectors shall all be of the UL ® 1686 C1 Style 1 pin-and-sleeve 4-pin type with metallic housings. The typical 25-30 foot cable is made up of four or five 3/0 AWG conductors in a Type W, UL ® sheath (engines that are capable of three-phase operations will have 5-conductor cable).
Existing 50 and 60 A (and other sizes besides 30, 100 and 200 A) older connection devices may be retrofitted to conform to this document as money is available and by attrition to conform to this section. Until "migration" to the new standard is complete, it may be necessary to make adapter cords to match up old engines with new receptacles, and vice-versa.
Custom buildings should be provided with a commercial power cabinet or panel, a transfer system, and a distribution panel that receives its power from the transfer system. This arrangement allows nonessential loads to be eliminated from the standby power load.
Variations in sites require power load calculations based on each individual installation.
Portable engine inlets at custom buildings should be sized for the ultimate power requirement of that installation. The -48/24 Volt bulk DC power plant load should be calculated based on all rectifiers being in operation at full rated output (recharge).
During a power failure, the engine-alternator will have to provide power for the equipment and the recharging of the batteries, and usually the HVAC system too.
In some cases, the AC service size sold by the electric utility is much larger than what we need. For example, we may only need a 30 A plug on an RT cabinet, but the Power
Company gives us a 100 A service. This is generally not a problem because the power pedestal is equipped with separate breakers for the incoming AC service and the portable engine plug. However, some local regulators insist that the portable engine plug be the same size as the service. These cases should be handled individually.
Generally, size the receptacle for the expected future maximum site load, rounding up to the nearest of the 4 standard Ampere sizes noted in this section. It won’t necessarily be the same size as the incoming commercial AC service from the Power Company.
Portable engine receptacles and tap boxes on buildings shall be marked for voltage, phases, phase rotation (for 3-phase sites), and Ampere rating.
Sequenced instructions for implementing standby power operation should be posted in all buildings served by a portable genset.
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Most 3-phase sites will have forward phase-rotation (A-B-C rotation). However, there are some sites where the commercial feed and all motors in the building will be wired with reverse rotation (C-B-A). As a general standard, all three-phase alternators, cords, and plugs should be wired for forward rotation. Sites with reverse rotation shall have the wiring between the portable engine plug and the transfer system configured so that the forward rotation from the generator becomes reverse rotation at the transfer system.
It is useful to label 3-phase sites served by portable generators with the phase rotation scheme at the portable genset inlet plug/receptacle on the building.
UL ® 2201 requires small portables less than 15 kW to have the engine frame and the neutral bonded at the set, making them “separately-derived”. However, they usually serve sites having a “hard-wired” neutral (non-separately-derived). This situation can be made safer by limiting genset distance from the site receptacle to 15’, and by ensuring that the receptacle is less than 10’ from the HSP MGN-ACEG bond. This is mostly not an issue, because most smaller gensets are not presently Listed to UL ® 2201.
Another option on some small portable gensets is the ability to open up their electrical panel and remove the bond.
All new portable genset inlet plugs/receptacles mounted to a structure should be labeled with whether the transfer system neutral is hardwired (the overwhelming majority of our sites), or has a switched neutral (for connection to a separately-derived portable engine-alternator. Only in the latter case (where the manual transfer switch switches the neutral) should a ground rod be driven at the engine-alternator, and assurances made that the portable alternator neutral and frame are bonded together.
NEMA L14-30P inlet four 10 AWG wires
Type W Sheath UL Power Cable
120/240 V
30 Amp
2-pole brkr.
Power Ped or RT pin 1 pin 2 pin 3 pin 4
NEMA
L14-30R
Connector
L1 BLACK
L2 RED
GREEN
WHITE (Neutral)
To Line 1 of
Alternator
To Line 2 of
Alternator
To Neutral
Lug of Alternator
To Chassis of
Engine Alternator
Engine/
Alternator
Figure 7-1: 30-Ampere Cable Hardwired to Single-Phase Engine-Alternator
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NEMA L14-30P inlet four 10 AWG wires
Type W Sheath UL Power Cable four 10 AWG wires
Eng/Alt Wiring pin 1
L1 BLACK
L2 RED pin 2 pin 3 pin 4 GREEN
WHITE (Neutral)
Power Ped or RT
NEMA
L14-30R connector
Chapter 7
Standby Engine-Alternators
L1 BLACK
L2 RED
WHITE
GREEN
NEMA
L14-30P
Plug
NEMA
L14-30R
Receptacle
120/240 V
30 Amp
2-pole brkr.
To Line 1 of
Alternator
To Line 2 of
Alternator
To Neutral
Lug of Alternator
To Chassis of
Engine Alternator
Engine/
Alternator
Figure 7-2: 30-Ampere Cable to Single-Phase Engine-Alternator Receptacle
Figure 7-3: 30-Ampere NEMA ® L14-30P Locking Connector Pin Configuration
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Reverse-Service
UL 1686 C1 Style 1
4-male-pin box & inlet with pin 3 pulled pin 1 four 2 AWG wires
Type W Sheath UL Power Cable
120/240 volt 100 Amp
2-pole breaker
L1 BLACK
PUB 77385
Issue K, July 2015 pin 2 pin 4
L2 RED
WHITE (Neutral)
GREEN
To Line 1 of
Alternator
To Line 2 of
Alternator
To Neutral
Lug of Alternator
To Chassis of
Engine Alternator
Power Ped or RT or hut or CO
UL 1686 C1 Style 1
Reverse-Service
4-female-pin connector
Engine/
Alternator
Figure 7-4: 100-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connector, Cable
Hardwired to Single-Phase Engine-Alternator
Reverse-Service
UL 1686 C1 Style 1
4-male-pin box & inlet with pin 3 pulled four 2 AWG wires
Type W Sheath UL Power Cable four 2 AWG wires
Engine Alternator Wiring
120/240 V 100 A,
2-pole brkr
L1 BLACK
To Line 1 of
Alternator
Power Ped or RT or
CO or hut
L1 BLACK pin 1
L2 RED pin 2
WHITE (Neutral) pin 4
GREEN
UL 1686 C1 Style 1
Reverse-Service
4-female-pin connector
L2 RED
WHITE
GREEN
UL 1686 C1
Style 1
4-pin Plug
UL 1686 C1
Style 1
4-pin Receptacle
To Line 2 of
Alternator
To Neutral
Lug of Alternator
To Chassis of
Engine Alternator
Engine/
Alternator
Figure 7-5: 100-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connectors, Cable to
Single-Phase Engine-Alternator Receptacle
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Reverse-Service
UL 1686 C1 Style 1
4-male-pin box & inlet with pin 3 pulled on single-phase sites five 2 AWG wires
Type W Sheath UL Power Cable
120/208 V wye or 240 V delta,
100 A, 3-phase brkr
(becomes 120/240 in single-phase operation)
L1 BLACK pin 1
L2 RED pin 2 pin 3 pin 4
L3 BLUE
WHITE (Neutral)
GREEN
Chapter 7
Standby Engine-Alternators
To Phase A or L1 of Alternator
To Phase B or L2 of Alternator
To Phase C of
Alternator
To Neutral
Lug of Alternator
To Chassis of
Engine Alternator
Engine/
Alternator
Power Ped or RT or hut or CO
Reverse-Service
UL 1686 C1 Style 1
4-female-pin connector
Figure 7-6: 100-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connector, Cable
Hardwired to Three-Phase or Single/Three-Phase Engine-Alternator
Reverse-Service
UL 1686 C1 Style 1
4-male-pin box & inlet
w/ pin 3 pulled on single-phase sites five 2 AWG wires
Type W Sheath UL Power Cable
L1 BLACK pin 1
L2 RED pin 2
L3 BLUE pin 3
WHITE (Neutral) pin 4
GREEN five 2 AWG wires
L1 BLACK
L2 RED
L3 BLUE
WHITE
GREEN
120/208 V wye or 240 V delta,
100 A, 3-phase brkr
(becomes 120/240 in 1-phase operation)
To Phase A or L1 of Alternator
To Phase B or L2 of Alternator
To Phase C of
Alternator
To Neutral
Lug of Alternator
Power Ped or RT or hut or CO
Reverse-Service
UL 1686 C1 Style 1
4-female-pin connector
UL 1686 C1
Style 1
4-pin Plug
UL 1686 C1
Style 1
4-pin Receptacle
To Chassis of
Engine Alternator
Engine/
Alternator
Figure 7-7: 100-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connectors, Cable to
Three-Phase or Single/Three Phase Engine-Alternator Receptacle
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Figure 7-8: 100/200-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve Receptacle
Front-View Pin Configuration
IEC 60309 orange plastic sleeve
4-male-pin box & inlet four 2 AWG wires
Type W Sheath UL Power Cable
120/240 volt 100 Amp
2-pole breaker
L1 BLACK
To Line 1 of
Alternator
L2 RED
WHITE (Neutral)
GREEN
To Line 2 of
Alternator
To Neutral
Lug of Alternator
To Chassis of
Engine Alternator
Power Ped or RT or hut or CO
IEC 60309
4-female-pin connector
Engine/
Alternator
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Figure 7-9: 100-Ampere IEC 60309 Orange Plastic-Sleeve 4-Pin Connector, Cable
Hardwired to Single-Phase Engine-Alternator
PUB 77385
Issue K, July 2015 four 2 AWG wires
Type W Sheath UL Power Cable
IEC 60309 orange plastic sleeve
4-male-pin box & inlet
L1 BLACK
Power Ped or RT or
CO or hut
L2 RED
WHITE (Neutral)
GREEN
IEC 60309
4-female-pin connector
Chapter 7
Standby Engine-Alternators four 2 AWG wires
Engine Alternator Wiring
120/240 V 100 A,
2-pole brkr
L1 BLACK
L2 RED
WHITE
GREEN
IEC 60309
4-pin Plug
IEC 60309
4-pin Receptacle
To Line 1 of
Alternator
To Line 2 of
Alternator
To Neutral
Lug of Alternator
To Chassis of
Engine Alternator
Engine/
Alternator
Figure 7-10: 100-Ampere IEC 60309 Orange Plastic-Sleeve 4-Pin Connectors, Cable to
Single-Phase Engine-Alternator Receptacle
Figure 7-11: IEC 60309 Orange Plastic Sleeve 100 Amp Receptacle Pin Configuration
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Reverse-Service
UL 1686 C1 Style 1 metallic-sleeve
4-male-pin box & inlet with pin 3 pulled four 3/0 wires
Type W Sheath UL Power Cable pin 1
L1 BLACK
L2 RED pin 2
120/240 volt 200 Amp
2-pole breaker
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Issue K, July 2015
To Line 1 of
Alternator
To Line 2 of
Alternator pin 4
WHITE To Neutral
Lug of Alternator
GREEN
Power Ped or RT or hut or CO
Reverse-Service
UL 1686 C1 Style 1
4-female-pin connector
To Chassis of
Engine Alternator
Engine/
Alternator
Figure 7-12: 200-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connector,
Cable Hardwired to Single-Phase Engine-Alternator
Reverse-Service
UL 1686 C1 Style 1 metallic-sleeve
4-male-pin box & inlet with pin 3 pulled pin 1 pin 2 four 3/0 wires
Type W Sheath UL Power Cable
L1 BLACK
L2 RED
4 - 3/0 wires
L1 BLACK
L2 RED
120/240 V,
200 A,
2-pole brkr
To Line 1 of
Alternator
To Line 2 of
Alternator pin 4
WHITE (Neutral)
GREEN
WHITE
GREEN
To Neutral
Lug of Alternator
Power Ped or RT or hut or CO
Reverse-Service
UL 1686 C1 Style 1
4-female-pin connector
UL 1686 C1
Style 1
Plug
UL 1686 C1
Style 1
Receptacle
To Chassis of
Engine Alternator
Engine/
Alternator
Figure 7-13: 200-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connectors,
Cable to Single-Phase Engine-Alternator Receptacle
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Reverse-Service
UL 1686 C1 Style 1
4-male-pin box & inlet with pin 3 pulled on single-phase sites five 3/0 wires
Type W Sheath UL Power Cable
120/208 V or 240 V delta,
200 A, 3-phase brkr
(becomes 120/240 in 1-phase operation)
L1 BLACK pin 1
L2 RED pin 2
L3 BLUE pin 3
WHITE pin 4
GREEN
Chapter 7
Standby Engine-Alternators
To Phase 1 of
Alternator
To Phase 2 of
Alternator
To Phase 3 of
Alternator
To Neutral
Lug of Alternator
To Chassis of
Engine Alternator
Engine/
Alternator
Power Ped or RT or hut or CO
Reverse-Service
UL 1686 C1 Style 1
4-female-pin connector
Figure 7-14: 200-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connector,
Cable Hardwired to Three-Phase or Single/Three-Phase Engine-Alternator
Reverse-Service
UL 1686 C1 Style 1
4-male pin box & inlet with pin 3 pulled on single-phase sites
Power Ped or RT or hut or CO five 3/0 wires
Type W Sheath UL Power Cable pin 1
L1 BLACK
L2 RED pin 2
L3 BLUE pin 3
WHITE (Neutral) pin 4
GREEN
Reverse-Service
UL 1686 C1 Style 1
4-female-pin connector five
3/0 wires
L1 BLACK
120/208 V or 240 V delta,
200 A, 3-phase brkr
(becomes 120/240 in 1-phase operation)
To Phase 1 of
Alternator
L2 RED
L3 BLUE
WHITE
GREEN
UL 1686 C1
Style 1
Plug
UL 1686 C1
Style 1
Receptacle
To Phase 2 of
Alternator
To Phase 3 of
Alternator
To Neutral
Lug of Alternator
To Chassis of
Engine Alternator
Engine/
Alternator
Figure 7-15: 200-Ampere UL ® 1686 C1 Style 1 Metallic-Sleeve 4-Pin Connectors,
Cable to Three-Phase or Single/Three-Phase Engine-Alternator Receptacle
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Chapter 8
PSMCs and Battery Monitors
CONTENTS
Chapter and Section
8.
Page
Power System Monitor/Controller (PSMC) and Battery Monitors ..................... 8-1
8.1 General .............................................................................................................. 8-1
8.2 Standard Monitor and Control Points ......................................................... 8-2
8.2.1
8.2.2
8.2.3
8.2.4
8.2.5
8.2.6
8.2.7
8.2.8
8.2.9
Primary Power Plant ................................................................... 8-2
Rectifiers ........................................................................................ 8-3
Batteries ......................................................................................... 8-4
Converter Plants ........................................................................... 8-5
Inverters ......................................................................................... 8-5
Residual Ringing Plants ............................................................. 8-6
Uninterruptible Power Supplies (UPS) ..................................... 8-6
Standby Engines and Transfer Systems .................................... 8-6
AC Power ...................................................................................... 8-8
8.3 Alarms .............................................................................................................. 8-8
8.4 Statistical Channels ......................................................................................... 8-9
8.5 Energy Management and Sequencing ......................................................... 8-9
8.6 Requirements of a PSMC for Small Sites, or Battery Monitor for UPS ... 8-9
8.6.1
8.6.2
8.6.3
Primary Power Plant ................................................................. 8-10
Rectifiers ...................................................................................... 8-10
Batteries ....................................................................................... 8-11
8.7 Power Alarms in Sites Without a PSMC ................................................... 8-12
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8. Power System Monitor/Controller (PSMC) and Battery Monitors
Chapter 8
PSMCs and Battery Monitors
8.1 General
The Power System Monitor/Controller (PSMC) provides front-end status for power plants in CenturyLink. Control functions (of the DC plant rectifiers) must be provided only when the power monitor is designed as an integral part of the DC power plant controller. It is recommended that each battery plant have its' own PSMC; however every office should have at least one PSMC for power alarming and monitoring.
The PSMC shall be equipped for IP communication that can be simultaneously accessed even when alarm system channels are operating. Preferably, there will also be backup dialup access in case the IP connection is lost. Although there may be a proprietary interface, there must also be a dumb-terminal, menu-driven VT-100 interface for the dialup and/or IP telnet access (each of which must be password-protected). IP interfaces should be through standard html web browser pages rather than proprietary interfaces.
The monitor should have an RS-232, USB, or IP interface such that it can be accessed locally by connection of a cable to a laptop.
All modems/DSUs and PADs shall be DC only. AC modems/DSUs and PADs are not used within CenturyLink ™ (an exception is allowed for UPS battery monitors backed up by the UPS) unless powered by a DC-plant backed inverter.
For PSMCs that will be used in locations where NMA ® is the ultimate aggregating alarm system, the PSMC should be NMA ® -compatible and support the CenturyLink ™
TL1 recommended Power message set (see Chapter 13) via X.25 protocol standards (TL1 over IP is optional). IP-addressable PSMCs and Battery Monitors may optionally report SNMP traps and be tested through Telcordia’s OSMINE ™ Light process so that a template is available for loading into NMA ® that translates between SNMP and TL1.
Control functions must not be accessible via dialup access without a special password
(typically known as a “super-user” password, which should be changed on initial installation from its default, with the new password reported to the CenturyLink ™
Power Tech Support person responsible for the area). The installation provider is responsible for verifying that all the alarms are reporting to the proper alarm center, and note the center responses on the proper form from Chapter 15.
When a larger distribution fuse/breaker doesn’t have a shunt, and monitoring is required, the use of a split core transducer is desirable. If the BDFB has a shunt then it is an option to monitor the BDFB load from that shunt. If the CenturyLink ™ Engineer makes a decision that, a transducer cannot be used or the distance to the BDFB is too great then that CenturyLink ™ Engineer can waive the requirement for monitoring the
BDFB load current, and should note this in the job package.
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Alarm and monitor leads (wireless communication for monitoring devices isn’t allowed in COs and larger long-haul sites, and is discouraged in smaller sites) don’t require fiber tags, but it is desirable to mark them on both near and far end for source/termination.
Where plant LVDs or EPOs exist in a plant, the PSMC shall be connected on the hot side of the disconnect point (unless the AHJ objects to this in a site with an EPO). Where power distribution from more than one nominal -48 VDC plant exists on the same floor, it is desirable for reliability to power standalone power monitors from a plant other than the one they are monitoring.
8.2 Standard Monitor and Control Points
The following sequence details the desired order of points for equipment to be monitored by the PSMC when a new monitor is placed. Note that battery monitors may only monitor the battery portions of the list below (including UPS batteries).
• -48 Volt battery plants
• 24 Volt battery plants
• 130 Volt battery plants
• 24 Volt converter plants
• 48 Volt converter plants
• 130 Volt converter plants
• Ringing plants
• Inverter plants
• Uninterruptible Power Supply (UPS) systems
• Standby engines
• Commercial AC
Many of the monitoring points for standby engines and commercial AC may be furnished as part of the transfer system. The requisition should list the exact equipment to be monitored and what is to be monitored on each unit of equipment.
The subsections below list required points to monitor (if possible). Monitor optional points when the PSMC has the capacity, or if directed by the CenturyLink ™ Engineer.
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8.2.1. Primary Power Plant
• Analog Points
— Plant voltage
— Plant current
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— Collocation feeder orders greater than (but not equal to) 60 Amperes
(basically 80 A and larger fuses or breakers)
— BDFB feeder current
— Current of PDF feeders greater than 100 Amperes (optional)
— Current feeding inverters (optional)
• Binary Points
— Distribution fuse/breaker alarm (FA)
— High DC Plant Voltage (HVA) – this may be derived from the analog voltage via a threshold
— Low Voltage / Battery on Discharge (BOD) – this may be derived from the analog voltage via a threshold
Very Low Voltage (optional, except in some Legacy CenturyLink ™ companies, where it is required)
— Low Voltage Disconnect (LVD), if installed (preferably in series with batteries)
— Plant major alarm (this is generally only an output from the PSMC to an alternate alarm system, and not an input into the PSMC)
— Plant minor alarm (this is generally only an output from the PSMC to an alternate alarm system, and not an input into the PSMC)
NOTE: The power plant major and minor from the standard controller may be run to a power monitor, but it’s better to parallel them with PSMC major and minor on the primary alarm device in case the PSMC fails.
8.2.2 Rectifiers
• Analog Points
— Rectifier current, when spare monitor points are available
• Binary Points
— Rectifier Fail (RFA) – Individual RFAs are required unless the controller or monitor has the ability to escalate from minor (single rectifier) to major (multiple rectifiers)
— High Voltage ShutDown (HVSD) – this may be via the rectifiers and/or DC plant controller
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For PSMCs that are also the power plant controller, the following control functions will be available from the controller to the rectifiers:
• Re-start (RS)
• Shutdown (TR)
• Sequencing (usually not used)
• Energy Management
8.2.3 Batteries
• Analog Points
— String current – A shunt (minimally sized per Section 3.10) will be placed in each new flooded battery string in DC plants to monitor charge and discharge current (this may be pulled off the shunt on a battery disconnect breaker if it exists). String current is optional for
VRLA and Lithium-based battery strings. A Hall Effect sensor may optionally be used in place of a shunt, especially for measuring float current. In UPS systems, AC ripple current is commonly measured by use of a split-core CT/transducer.
— Room temperature – One temperature sensor will be placed to monitor room temperature, approximately five feet above the floor in the area of the batteries. It must be placed away from heating and cooling sources, such as rectifiers, and HVAC vents.
— Single cell Voltage – The voltage of at least one flooded cell (typically known as the pilot cell) will be monitored per plant.
— Cell Temperature – Flooded batteries require one temperature sensor to be placed, to monitor the temperature of one cell per plant (typically the same as the pilot cell used for single-cell voltage). VRLA batteries require multiple temperature sensors to monitor the temperature of a cell/block in each string. A function channel should be established for
VRLA batteries to monitor the differential between cell/monobloc temperatures and ambient. If there is no cell temperature monitoring for VRLA batteries in controlled environments, and temperature compensation from the power plant controller has a deadband (see
Table 13-16), then temperature compensation may be alarmed as a minor alarm; otherwise temp comp should not be alarmed.
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— Internal Cell/Monobloc Impedance – The internal resistance, conductance, or impedance of VRLA batteries may optionally be measured (with an adjustable daily-monthly measurement period). It usually applies to VRLA UPS batteries, but can be used for other leadacid batteries (especially VRLA) where the PSMC/monitor is capable.
— Mid-point Voltage – Measure the voltage at the midpoint of each battery string (optional).
• Binary Points
— Battery String Disconnect (which may be internal, especially on Li-ion batteries) breaker tripped or turned off (if installed — this may be daisy-chained to one point from multiple disconnects, and should be wired in series from the normally closed contacts for Li batteries).
— Battery (String) Major (for batteries with a BMS, or coming from a battery monitor)
— Battery (String) Minor (if it exists for batteries with a BMS, or coming from a Battery monitor)
8.2.4 Converter Plants
• Analog Points
— Voltage
— Current (if shunts are already installed)
• Binary Points
— Distribution Fuse fail (possibly both major and minor alarms)
— Converter Plant Major (if available)
— Converter Plant Minor (if available)
— Individual Converter Fail Alarms (CFA) — only required if Plant
Major/Minor are not available
8.2.5 Inverters
• Analog Points (Optional)
— AC Voltage (per phase, line to neutral)
— Current (per phase)
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PSMCs and Battery Monitors
• Binary Points
— Inverter Fail/Major alarm
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— Minor alarm
— Inverter off normal (indicates when a DC-preferred inverter is in ACpreferred mode or bypass, or when an AC-preferred inverter is in maintenance bypass)
— Bypass Not Available (when bypass is used – optional for less critical systems)
8.2.6 Residual Ringing Plants
• Binary Points
— Minor (single ring generator or interruptor failure)
— Major
— Distribution Fuse Alarm (if available – if not, it must be part of the major or minor alarm)
8.2.7 Uninterruptible Power Supplies (UPS)
• Analog Points (Optional)
— AC Voltage (per phase, line to neutral)
— Current (per phase)
• Binary Points
— UPS Fail/Major
— UPS Battery on Discharge and/or Low Voltage
— EPO Activated (for sites with an EPO)
— Mode indicator (indicates when UPS an on-line UPS is in lineinteractive mode or bypass, or when a line-interactive UPS is in maintenance bypass)
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8.2.8 Standby Engines and Transfer Systems
These points should be installed on a going forward basis. Older engines and control equipment may not be capable of all of these points.
• Analog Points
— Start Battery Voltage (optional if Start Battery Charger Fail alarm installed)
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— Engine Temperature (if available it is optional)
Chapter 8
PSMCs and Battery Monitors
— Engine Oil Pressure (if available it is optional)
— Engine Room Temperature (measured inside the room, not on the outside wall – optional)
• Binary Points
— Engine Run
— Engine Switch Off Normal
— Engine Breaker Open (optional)
— Engine Emergency Stop
— Fuel Heater Fail (when a fuel heater exists - optional)
— Engine Supplying Load or Transfer Switch Proper Operation (optional or filtered in some CenturyLink ™ entities)
— Single-Phase Lockout (for transfer switches equipped with this feature)
— Engine Fail/Major (generic – use if there are not individual alarms as described below – Engine Fail may be broken out separately)
1.
Low Oil Pressure (Optional)
2.
Overcrank (Optional)
3.
Overspeed (Optional)
4.
High Coolant Temperature (Optional)
5.
Start Battery Charger Fail (Optional if Start Battery Voltage installed)
— Engine Minor (generic – use if there are not individual alarms as described above and below)
1.
Load Transfers (Optional)
2.
Transfer System and/or Engine Controls not set to Automatic
(off Normal)
3.
Block Heater Alarm or Low Coolant Temperature
— Engines Failed to Parallel (for paralleled systems)
— Fuel System Trouble (or individual alarms below)
1.
Low Fuel (this may be combined into the Fuel System Trouble, and if there is a Day Tank, it too should be alarmed for this)
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2.
Fuel Leak (this may be combined into the Fuel System Trouble) or Tank Leak (including interstitial space for all direct-buried tanks and any aboveground or underground vaulted tank where the total site fuel storage capacity is ≥ 1320 gallons)
3.
Overfill (can be combined with the Fuel System Trouble Alarm, but in any case, it is required on all direct-buried tanks and aboveground or underground vaulted tanks where total site fuel storage capacity is equal to or larger than 1320 gallons)
8.2.9 AC Power
• Analog Points (facilities with multiple transfer switches shall be equipped with voltage and current monitoring at the load side of each transfer switch serving critical power and/or HVAC systems)
— AC Voltage per phase/leg – measured phase-neutral, and monitored on the transfer system load side (it is desirable for the PT voltage stepdown transformers to be fused or breaker-protected for ease of replacement)
— AC current per phase/leg – monitored on the transfer system load side
• Binary Points
— AC fail (although there should be one alarm, individual sensors per phase are desired, if possible). This should be monitored on the line side of the transfer system (at the main disconnect if possible). The relay shall be served from a fuse or breaker to allow for servicing.
— TVSS alarm (indicates when the TVSS has failed or is degraded – may not be available on older surge suppressors).
— Ground Fault detection (larger systems may detect a large ground fault on the incoming commercial AC, the engine, or large branch circuits)
8.3 Alarms
If the PSMC fails, local visual and audible alarms will not be disabled when control is passed to the traditional power plant controller.
The PSMC will analyze incoming alarm information from the power plant components and provide settable downstream alarm levels (thresholds) as required (see Chapter 13).
If the PSMC is an alarm-transmitting device, it will also report at least major, minor, and monitor fail (watchdog) alarms to another alarming system, as a backup to the
X.25/IP TL1 communications or to the SNMP over IP communications.
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8.4 Statistical Channels
Chapter 8
PSMCs and Battery Monitors
The PSMC will be capable of storing statistical data for engineering power plants.
There will be a minimum of ten statistical channels supplied with the PSMC. Any analog channel can be assigned for statistical data. Each statistical channel will be capable of storing peak high, hourly average high, daily low and hourly average low for each day while the channel is active. This data will be retained daily for a minimum of
30 days.
8.5 Energy Management and Sequencing
The PSMC will not be wired for power plant or engine control, unless the PSMC is also the power plant controller (then it may control the rectifiers, including energy management and rectifier sequencing).
The power plant controller shall provide energy management for ferroresonant rectifiers as follows:
• The power plant controller will activate sufficient rectifier capacity per controlled plant to support the presented load.
• When energy management is active, the power plant controller will ensure that each rectifier in each controlled plant is active for a minimum of 4 hours during each 30-day period.
• Sequencing priority will be individually selectable by rectifier.
The power plant controller will be capable of providing rectifier restart sequencing upon restoral of AC power. The sequencing should be separately controllable for transitions to commercial AC versus the standby engine. If the transition scheme will not allow two configurations, then the transition scheme must be based on the capability of the standby engine. Sequencing is not normally employed except in cases of overloaded engines or closed transition transfer switches.
8.6 Requirements of a PSMC for Small Sites, or Battery Monitor for UPS
A PSMC or Battery Monitor for Confined Locations (PSMC-CL) may exist to perform monitoring for locations in CenturyLink ™ smaller than COs or other large installations; or a permanent battery monitor is common for larger UPS applications. A PSMC-CL is optional. A PSMC-CL may be the same unit as that used for a PSMC in COs, but equipped with fewer points.
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A PSMC-CL should (shall if it doesn’t have an IP interface) be equipped for remote access dialup capabilities. Although it may have a proprietary interface on dialup and local RS-232 access, it must also present a dumb-terminal VT-100 menu-driven interface.
The PSMC-CL's modem shall automatically adjust baud rate to match the baud rate of the originating modem with no parity, 8 bits, and 1 stop bit (N81). The PSMC-CL may be capable of TL1 over X.25 or IP, or SNMP via IP, but it is not required. An external battery monitor for UPS systems shall be IP-equipped (some UPS manufacturers build battery monitoring into their UPS – in those cases, it is also desirable that the battery monitoring and alarms be transmitted via IP, but at a bare minimum, alarms must be provided via dry Form C contacts), and is not necessarily required to have a dialup modem.
The PSMC-CL shall be password protected. Multiple access levels with “super user” capabilities must be provided in order to make database changes.
The PSMC-CL shall report Power Major, Minor, and watchdog alarms, via dry form C contacts, to the alarm telemetry of the site.
If a PSMC-CL or UPS battery monitor is installed, it should be able to monitor up to 6 battery strings, including the required monitor points specified in the sub-sections below (assume the point is required unless otherwise specified – note that only the battery points are required for battery-only monitors):
8.6.1 Primary Power Plant
• Analog Points
— Plant Voltage
— Plant Current
• Binary Points
— Low Voltage (also known as “battery on discharge)
— High Voltage
— Power Distribution Fuse/Breaker Fail
8.6.2 Rectifiers
• Binary Points
— Rectifier Fail (may be both minor for single rectifier fails, and major for multiple rectifier failures)
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8.6.3 Batteries
Chapter 8
PSMCs and Battery Monitors
• Analog Points (this can include engine start/control batteries in sites with permanent engines and battery monitors – especially UPS battery monitors)
— Voltage – Voltage monitoring can be placed on pilot cells/monoblocks
(optional)
— Cell Temperature – One temperature sensor will be placed to monitor the temperature of a "reference" battery in each battery string; preferably the most negative cell on the highest row of the string. If the plant employs temperature compensation, additional probes run to the monitor are not necessary.
— Room Temperature – Only one temperature sensor will be placed to monitor room (or cabinet) temperature. The sensor should not be placed next to a heating or cooling source. String bulk charge/discharge current – A shunt (which may be a part of a disconnect breaker) may be placed in each battery string to monitor charge and discharge current (optional).
— String float current – A Hall effect sensor (shunts are not sensitive enough) may be placed to monitor string float current (optional). For
UPS systems, a CT can monitor AC ripple current.
— Internal Cell/Monobloc Impedance – The internal resistance, conductance, or impedance of VRLA batteries may optionally be measured (with an adjustable daily-monthly measurement period).
• Binary Points
— Temperature differential / thermal runaway – the difference between ambient and cell temperature, set to alarm at a certain threshold (per
Chapter 13). This may be a function channel programmed in the monitor.
— Battery String Disconnect breaker tripped or turned off (if installed — the alarm may be daisy-chained to produce one alarm from multiple disconnects).
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8.7 Power Alarms in Sites without a PSMC
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When there is no PSMC for the site the following binary alarms should be connected to the alarm device on site as a minimum (some older power systems may not have all of these alarms available). When there are older overhead bitstream housekeeping miscellaneous environmental alarm systems that do not have enough points, alarms should be combined (minimum of two – major and minor) onto the available points.
• DC Plant alarms
— Major
Includes multiple rectifier fail
Includes main distribution fuses (can be a separate alarm)
Includes High DC Plant Voltage (can be a separate alarm)
— Minor (including a single rectifier failure, which can be separate)
— Low Voltage (also known as “battery on discharge”)
Very Low Voltage (optional in some CenturyLink ™ entities)
— Low Voltage Disconnect (in the rare cases where used)
— Battery Disconnect (when used)
— High Voltage Shutdown (HVSD)
— Converter Plant Distribution Fuse / Major Alarm (also applies to multiple converter failures – only applicable for sites with converter plants)
— Converter Plant Minor / Individual Converter Failure (only applicable to sites with converter plants
• Miscellaneous Power System alarms
— Ring Plant Major
Includes multiple ringers failed
Includes ring plant distribution fuses (can be a separate alarm)
— Ring Plant Minor / single Ring Generator / Interrupter Failure
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• AC system alarms
— Commercial Power Fail (at main disconnect if possible)
Chapter 8
PSMCs and Battery Monitors
— Surge Arrestor Fail (TVSS/SPD)
— ATS SystemNot in Auto (when there’s a permanent engine on site)
— Single-Phase Lockout (when transfer switch is so-equipped)
— AC system Ground Fault Detection (when equipped)
— Inverter on Bypass (for systems with a bypass)
— Inverter Bypass Not Available (for the most critical systems)
— Inverter Fail/Major
— UPS on Bypass (for sites with UPS)
— UPS Battery on Discharge or Low Voltage (for sites with UPS)
— UPS Fail/Major (for sites with UPS
• Engine alarms (when there’s a permanent engine on site)
— Engine Run
— Engine Fail (can be a combination of many alarms)
— Engine Emergency Stop (can be combined with the Engine Fail)
— Low Fuel (can be part of Fuel System Trouble – both day and main tanks)
— Fuel Leak / Fuel System Trouble – from fuel monitor if available
— Engine Start Battery Charger Fail and/or Engine Battery Low Voltage
— Engine Controls Not in Auto
— Engines Failed to Parallel (for large paralleling systems)
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Chapter 9
DC Power Distribution
CONTENTS
Chapter and Section
9.
Page
DC Power Distribution ............................................................................................... 9-1
9.1 General .............................................................................................................. 9-1
9.2 Telecommunications Equipment Loads ...................................................... 9-1
9.3 Power Plant Distribution Characteristics .................................................. 9-13
9.4 Cabling and Bus Bar ..................................................................................... 9-14
9.5 Protectors and Cable Sizing ......................................................................... 9-19
9.6 DC System Fuse and Breaker Sources ....................................................... 9-21
9.7 Bus Bar Labeling and Layouts .................................................................... 9-32
Tables
9-1 Bus Bar Ampacity for Single Bars ............................................................................. 9-9
9-2 Bus Bar Ampacity for 2-4 Bars per Polarity in Parallel ....................................... 9-10
9-3 Bus Bar Ampacity for 5-12 Bars per Polarity in Parallel ..................................... 9-11
9-4 Power Wire Ampacities ........................................................................................... 9-12
TOC 9-i
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Figures
9-1 Batteries to Main Distribution Voltage Drops Via MTBs ...................................... 9-5
9-2 Batteries to DC Plant Voltage Drops Where There is No Centralized Shunt .... 9-5
9-3 Power Plant Distribution to BDFB Voltage Drops ................................................. 9-6
9-4 PBD to BDFB (via Remote A/B PBDs) Voltage Drops .......................................... 9-6
9-5 Power Plant to BDFB (via a Single Remote PBD) Voltage Drops ........................ 9-7
9-6 BDFB to Equipment Bay Voltage Drops .................................................................. 9-7
9-7 Power Plant Distribution Direct to Equipment Bay Voltage Drops .................... 9-8
9-8 Bus Bars with Bar Width Vertical and Spaced ≥ Bar Thickness ........................... 9-8
9-9 Bus Bars run Flat ....................................................................................................... 9-13
9-10 Vertically Run Bus Bars ............................................................................................ 9-13
9-11 Typical Mounting of a Bus Bar above PDFs and Battery Stands ....................... 9-19
9-12 Splitting the Voltage Drop when a Top-of-Bay Fuse Panel Serves
Equipment More Than One Bay Away ................................................................. 9-22
9-13 BDFB Fuse Assignment Label ................................................................................. 9-25
9-14 Typical Layout of BDFB Fuse Panels ..................................................................... 9-26
9-15 Typical Layout of 2 Load 600 Ampere BDFB........................................................ 9-27
9-16 Typical Layout of 4 Load 400 Ampere BDFB........................................................ 9-28
9-17 Typical Return Bus Bar Mounting for a 7’ BDFB (View A-A) ............................ 9-29
9-18 Typical Return Bus Bars Mounting for a 7’ BDFB (View B-B) ........................... 9-30
9-19 Load and Embargo Labels for BDFBs .................................................................... 9-31
9-20 Example of Bus Bars (Term Bars) above a Battery Stand .................................... 9-32
9-21 Example of a Battery Return Bus Bar above a BDFB ........................................... 9-33
9-22 Chandelier Hot Side Main Terminal (Term) Bar .................................................. 9-33
9-23 Chandelier Return Side Bar ..................................................................................... 9-33
9-24 Example of a Remote Ground Window ................................................................ 9-34
9-25 Example of a Main Return / Ground Window MGB Bar ................................... 9-34
9-26 Example of Sandwiched Terminations .................................................................. 9-34
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9. DC Power Distribution
9.1 General
Chapter 9
DC Power Distribution
CenturyLink ™ is responsible for the floor plan(s) layout of a site. Layouts of equipment shall be per CenturyLink ™ Technical Publication 77351, CenturyLink ™ Standard
Configuration Documents, and Telcordia ® GR-63, as required.
9.2 Telecommunications Equipment Loads
The total load fed by the DC distribution system is determined by the type, quantity, and mix of telecom equipment in a site. Once the load is determined, it is matched to a distribution system and a power source with adequate capacity to power the loads and the distribution losses. The power cable is sized per the voltage drop guidelines of this section (once DC power has been handed off to a CLEC [typically at their fuse panel], voltage drop rules are of their own choosing from that point downstream, although following the voltage drop rules of this section maximizes battery reserve time to their equipment). Ampacity of the cable shall equal or exceed the fuse or breaker size.
Nominal voltages for standard telecom equipment are 24, 48, and 130 VDC. Operating voltage limits permitted on individual equipment assemblies are more variable. For example, NEBS ™ specifies that nominal -48 VDC equipment must work from -42.64 to
-56 V. However, some old equipment won’t work at -56 V (e.g., some might only work to -53.5), while more modern equipment might work above it (60 V, for example). Most equipment will work down to at least -42.64 V, and some will work even lower.
The formula for calculating voltage drop is:
CM
=
K
×
I
× d
V
D where,
CM is Circular Mils (see Tables 9-1 through 9-4 for bus bar and wire)
I is Amperes – 125% of the List 1 drain if known, or one of the following:
— half the protector size for feeds to a BDFB/BDCBB
— CLEC power feed order if the CLEC does not provide List 1 drain
— 4 or 8 hour battery discharge rate for runs from a battery stand to main term bars / chandelier, or plant buses where there is no MTB
— The PBD busbar rated ampacity for MTB to a PBD hot bus runs
— The shunt size for runs from the MTB to a PBD return bus
— 80% of the protector size in all other cases (split that load for true
A/B-fed equipment)
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K is 11.1 for copper and 17.4 for aluminum at approximately 40°C
(typical cable rack temperature) d is distance (for distribution, this is top-to-top distance and does not include the drop cabling into or out of equipment or distribution bays
– distance may be loop or one-way – see the bullet items and Figures of this section for further guidance)
V
D
is the voltage drop maximum as described in the rest of this section
The requirements for distribution voltage drop, and which drains to use for sizing are specified below, and illustrated in Figures 9-1, through 9-7. These Figures and the bullets are designed around nominal -48 V battery/rectifier plants (nominal -48 V is the
DC voltage that CenturyLink ™ provides to all CLECs, and to most CenturyLink ™ equipment). For nominal 24 V output battery plants, cut the voltage drops in half. For nominal 130 V output battery plants, double the allowable voltage drops. For converter plants without batteries attached to the output bus, the voltage drops can be much greater (follow the NEC ® note of maximum 5% voltage drop from the converter plant to the using equipment overall, with no more than 3% in any one branch).
• The 0.10 one-way voltage drop from the "chandelier" (MTB) negative bus to the primary power distribution boards/bays/panels, shall be calculated to the bus bar ampacity of the distribution bay/panel (unless the shunt capacity of the plant is less, in which case it may be calculated at the plant’s main shunt capacity). The
0.10 one-way voltage drop from the chandelier positive bus to the plant return bar(s) is calculated at the Amp rating of the shunt. The shunt(s) in the chandelier or PBDs also have a maximum voltage drop (typically 0.05 V — 50 mV).
• Battery cable from the battery strings to the main bus bar chandelier (MTB) shall be sized to either the 4 or the 8 hour 1.86 V/cell (for lead-acid cells) 100% discharge rate (4 hours for sites with permanent on-site auto-start, auto-transfer engines, and 8 hours for all other sites), using a 0.20 loop voltage drop. Where 2 strings exist on a stand (or the potential for two strings exists on a stand) that use common termination (term) bars for both strings (stand term bars are recommended for all battery stands to provide a convenient connect/disconnect point, especially for battery strings that don’t have disconnects), the 4 or 8 hour rate of the batteries is doubled for the voltage drop sizing between the bars.
Where even more strings exist or could exist in the stand (more typical with 12 V front-terminal battery stands/racks), size the cabling between the bars at the 4 or
8 hour rate of all the potential strings in the stand.
• For plants that do not have a "chandelier" MTB (all battery strings are cabled directly to the main buses above or internal to the PBDs), their cables are also sized at the 4, or 8 hour rates using a 0.2 V loop drop.
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• The switch manufacturer's recommended total List 2 drain for the PDF, with a
1.0 V loop voltage drop shall determine the cable size from the power board to the PDF. The manufacturers' recommended drain shall also determine the fuse or circuit breaker size for the power board. It is Switch Engineering/
Installation’s responsibility to run and size the battery feed and return cables from the main power board.
• The voltage drop, cable sizing, and drain from the switch secondary distribution
(PDF) to the switch bay shall be determined by the switch manufacturer.
• Any feeder from a power board to a BDFB/BDCBB should generally be protected based on a load of 225-400 Amperes for quadruple (4) loads or 6-load
BDFBs, or 400-600 Amperes for dual (2) loads. Exceptions can be made based on the size of the panels and the loads at the BDFB/BDCBB. The cable sizing for this loop should be computed based on half the protector size used as the drain.
However, cable ampacity shall always equal or exceed the protector size.
BDFB/BDCBB loads are limited to one half of the protector size on any one side of the feed (A or B, C or D, etc.) so that one side can carry the whole load if the other side fails and there is true redundancy in the equipment. For example, if we were feeding A and B panels on a BDFB/BDCBB with a protector size of 500
Amperes , the voltage drop calculation would be done at 250 Amperes (since any one side should normally not carry more than that). Cable ampacity would still need to equal or exceed 500 Amperes in this example.
• Each distribution fuse panel in a BDFB/BDCBB shall be individually fed. All feeds to a given BDFB/BDCBB shall originate in the same power plant. The conductor(s) shall be, at a minimum, sized for the protection device and be increased in size as required to allow the total voltage drop (calculated at half the protector size) to not exceed 0.5 Volts one way, or 1 Volt loop.
• The maximum allowable loop voltage drop from the BDFB/BDCBB to any facilities (non-switch) equipment shall be 0.5 Volts, based on 125% of the List 1 drain of the equipment that CenturyLink ™ expects to place in the bay.
— Follow the recommendations of the manufacturers of the equipment expected in a bay for the protector sizing for a bay receiving a miscellaneous fuse or breaker panel. Lacking that information, add up the expected List 2 drains of the equipment expected to be fed from that panel. Calculate the voltage drop cable sizing for the miscellaneous fuse panel based on 125% of the List 1 drain for the bay, or 80% (the inverse of the 125% protector sizing rule) of the feeder fuse or breaker size if List 1 is unknown (for true A/B loads, this current is halved to run the voltage drop calculation – see Section 2.4.1 for an example).
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DC Power Distribution
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— Note that most loads fed from miscellaneous fuse or breaker panels go to equipment that can switch from “A” to “B” if one supply fails. This will double the load on the remaining fuse panel supply fuse; so, the feeds to the panel must each have an ampacity to handle both loads.
The voltage drop calculation need only be sized for one load.
— Feeds to miscellaneous fuse panels feeding only DSX bays are exempt from voltage drop standards, and can be fed with wire meeting the minimum ampacity of the feeding fuse. These fuses feed only LEDs
(non-service-affecting) and a single feed miscellaneous fuse panel feeding many bays is the general method of providing power. Few
LEDs in the lineup will be on at any one time. To qualify for this exemption, the miscellaneous panel must be marked as “DSX Only”.
• Equipment fed directly from the power distribution board/bay (e.g., equipment in a smaller site, and/or equipment relatively close to a DC power plant) should have the cable sized based on 125% of the List 1 equipment drain provided by the manufacturer, and with a loop voltage drop of 1.5 V.
• In large sites, there may be remote PBDs. The voltage drops to these remote
PBDs can be balanced with the overall allowable voltage drop from the main
PBD to a BDFB or piece of equipment (in other words, part of the 1.0 V loop allowed from a main PBD to a BDFB can be “borrowed”), but in no case shall the overall voltage drop exceed the maximum allowed from the main PBD to the equipment. Along the same lines, for individual special cases, the power
Engineer can rearrange the voltage drops for which they are responsible
(battery to secondary distribution point typically) as long as overall voltage drop within that “loop” remains the same. However, when voltage drops for remote PBDs aren’t engineered per Figures 9-4 or 9-5, the Engineer must mark the voltage drops used both in the CenturyLink-authorized CAD system, and ensure that Installation marks it at the remote PBD in the field.
Every equipment bay and/or shelf which includes any Designed Services Circuits (coin,
ISDN, 56kb, FXS, FX0, DX , TO etc.), and/or DS-1/T1 (or higher data rate SONET) circuits must be fed independently from both the "A" and "B" power source (primary and/or secondary distribution). Equipment bays and/or shelves, which include only less than 1400 DS-0 and/or POTS circuits (or are carrying only non-regulated best-effort ethernet) are not required to have A and B feeds, although it is always desirable to have dual feeds for network traffic-carrying equipment.
Mounting of more than one wire/cable, terminal end on a single lug (commonly referred to as “double-lugging”) is prohibited. A splice or tap should be used instead.
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DC Power Distribution
Input power connections to the using equipment should be of a crimped lug type. If plastic connectors are used they shall not protrude from the front or rear of the equipment where they may be inadvertently knocked off or loosen.
Figure 9-1: Batteries to Main Distribution Voltage Drops Via MTBs
Figure 9-2: Batteries to DC Plant Voltage Drops where there is No Central Shunt
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Figure 9-3: Power Plant Distribution to BDFB Voltage Drops
9-6
Figure 9-4: PBD to BDFB (via Remote A/B PBDs) Voltage Drops
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Chapter 9
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Figure 9-5: Power Plant to BDFB (via a Single Remote PBD) Voltage Drops
Figure 9-6: BDFB to Equipment Bay Voltage Drops
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Figure 9-7: Power Plant Distribution Direct to Equipment Bay Voltage Drops
All new battery cables (both feed and return) from the battery bus bar to the main battery termination bus bar assembly (BTBA) chandelier (where one exists) will be sized per Figure 9-1. If a battery disconnect is required, size the battery cables using Chapter
3. It is suggested that unfused battery cables running to a battery stand term bar be sized as follows for larger batteries (realizing that the CenturyLink ™ Power Engineer can change this size in order to meet the voltage drop and ampacity requirements found previously in this section):
• Flooded Batteries 840 Amp hours to 1700 Amp hours: four 4/0 AWG
• Flooded Batteries over 1701 Amp hours: four 350 kcmil
Figure 9-8: Bus Bars with Bar Width Vertical and Spaced ≥ Bar Thickness
9-8
bar width
½"
¾”
2½"
3"
3½"
4"
6"
8"
1"
1½"
1”
1½"
2"
½”
1"
1½"
2"
2"
2½"
3"
4"
6"
8"
1”
1½”
2”
3”
4”
6”
8”
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-ness
1 /
8
"
¼"
3 /
8
"
½”
Table 9-1 Bus Bar Ampacity for Single Bars
Copper ampacity bar width vertical bar flat or vertically run
154 152
215 212
887
1,040
1,192
1,342
1,931
2,506
524
724
275
390
503
238
409
572
731
919
1,110
1,298
1,667
2,388
3,092
632
863
1,088
1,525
1,951
2,783
3,596
1,887
2,623
3,289
869
1,019
1,152
1,298
1,820
2,292
517
714
271
385
496
234
403
564
721
906
1,087
1,272
1,612
2,250
2,828
622
851
1,073
1,494
Aluminum ampacity bar width vertical bar flat or vertically run
114 112
159 157
651
762
873
982
1,408
1,823
387
533
203
287
370
177
302
421
537
675
814
951
1,219
1,740
2,248
466
636
800
1,118
1,427
2,029
2,615
1,376
1,899
2,366
636
746
841
946
1,320
1,649
381
525
200
283
364
174
297
415
529
665
796
930
1,175
1,629
2,035
459
626
788
1,093
Chapter 9
DC Power Distribution circular mils
79,600
Cu
µΩ
/ft
Al
µΩ
/ft
140 220
119,400 90 150
159,200 70 110
238,700 45 75
318,300 35 55
159,200 70 110
318,300 35 55
477,500 25 35
636,600 18 30
795,800 15 26
954,900 12 20
1,114,000 10 16
1,273,000 9 14
1,910,000 6
2,546,000 4
9
7
477,500 25 35
716,200 16 25
954,900 12 20
1,194,000 9 14
1,432,000 8 12
1,910,000 6 9
2,865,000 4
3,820,000 3
6
5
636,600 18 30
954,900 12 20
1,273,000 9 14
1,910,000 6 9
2,546,000 4
3,820,000 3
7
5
5,093,000 2 3.5
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Chapter 9
DC Power Distribution
Table 9-2 Bus Bar Ampacity for 2-4 Bars per Polarity in Parallel
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Issue K, July 2015
Copper ampacity
# bars bar thick
-ness
2
3
4
¼"
½"
¼"
½"
¼"
½"
8"
4"
6"
8"
2"
3"
4"
6"
8"
4"
6"
8"
2"
3"
4"
6" bar width
2"
3"
3"
4"
6"
8"
4"
6"
8"
2"
2,313
3,123
3,819
5,026
5,916
5,679
7,392
8,659
1,787
2,432
2,996
3,992
4,770
4,437
5,848
6,950 bar(s) flat or laminated or vertically run
1,259
1,735
2,163
2,937
3,583
1,902
2,577
3,182
4,275
5,189
2,426
3,394
4,328
6,130
7,872
6,384
8,933
11,395
1,865
2,616
3,342
4,745
6,105
4,918
6,902
8,824 bar width vertical and spaced
1,301
1,834
2,350
3,352
4,325
1,961
2,715
3,445
4,861
6,236
1,823
2,549
3,249
4,598
5,899
4,782
6,688
8,527
1,397
1,957
2,498
3,543
4,552
3,670
5,146
6,572
1,745
2,483
3,198
1,458
2,015
2,555
3,597
4,608
Aluminum ampacity bar width vertical and spaced bar(s) flat or laminated or vertically run
969
1,363
935
1,285
1,596
2,152
2,605
1,411
1,906
2,346
3,131
3,770
1,735
2,337
2,850
3,728
4,354
4,228
5,473
6,362
1,336
1,813
2,226
2,947
3,493
3,291
4,311
5,083 circular mils
Cu
µΩ
/ft
Al
µΩ
/ft
1,273,000 9 14
1,910,000 6 9
2,546,000 4
3,820,000 3
7
5
5,093,000 2 3.5
2,546,000 4 7
3,820,000 3 5
5,093,000 2 3.5
7,639,000 1.5 2.3
10,186,000 1.1 1.7
1,910,000 6
2,865,000 4
3,820,000 3
5,730,000 2
7,639,000 1.5 2.3
7,639,000 1.5 2.3
11,460,000 1 1.6
15,280,000 0.7 1.2
5
3
9
6
2,546,000 4
3,820,000 3
7
5
5,093,000 2 3.5
7,639,000 1.5 2.3
10,186,000 1.1 1.7
10,186,000 1.1 1.7
15,280,000 0.7 1.2
20,372,000 0.55 0.9
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Table 9-3 Bus Bar Ampacity for 5-12 Bars per Polarity in Parallel
Chapter 9
DC Power Distribution
# bars bar thick
-ness
5
6
7
8
9
¼"
½"
¼"
½"
¼"
½"
¼"
¼"
10 ¼"
11 ¼"
12 ¼"
6"
8"
6"
8"
6"
8"
6"
8"
6"
8"
6"
8"
6"
8"
6"
8" bar width
4"
6"
4"
6"
8"
4"
8"
4"
6"
8"
13,020
16,660
14,400
18,415
15,775
20,170
17,150
21,925
12,980
16,520
10,270
13,150
15,000
19,080
11,645
14,905
9,634
7,847
10,960
13,960
6,295
8,891
11,395
9,309
Copper ampacity bar width vertical and spaced bar(s) flat or laminated or vertically run
5,312
7,512
4,637
6,048
7,041
6,915
8,921
10,340
5,452
7,064
8,154
8,148
10,095
11,455
11,100
12,545
12,105
13,640
13,110
14,725
10,445
12,005
8,076
9,259
11,960
13,660
9,086
10,360
9,854
12,605
10,905
13,945
11,955
15,285
13,005
16,625
9,765
12,425
7,753
9,926
11,300
14,345
8,804
11,265
7,242
5,892
8,227
10,475
4,748
6,702
8,585
7,002
Aluminum ampacity bar width vertical and spaced bar(s) flat or laminated or vertically run
3,999
5,650
3,471
4,502
5,202
5,161
6,626
7,624
4,090
5,273
6,043
6,092
7,575
8,541
8,338
9,369
9,102
10,195
9,866
11,025
7,775
8,876
6,041
6,878
8,921
10,120
6,808
7,711 circular mils
Cu
µΩ
/ft
Al
µΩ
/ft
6,365,000 1.7 3
9,550,000 1.2 2
12,730,000 0.9 1.4
12,730,000 0.9 1.4
19,100,000 0.57 0.95
25,460,000 0.4 0.7
7,639,000 1.5 2.3
11,460,000 1 1.6
15,280,000 0.7 1.2
15,280,000 0.7 1.2
22,914,000 0.5 0.8
30,560,000 0.35 0.6
13,370,000 0.8 1.3
17,822,000 0.6 1
26,740,000 0.4 0.66
35,644,000 0.3 0.5
15,280,000 0.7 1.2
20,372,000 0.55 0.9
17,190,000 0.65 1
22,914,000 0.5 0.8
19,100,000 0.57 0.95
25,460,000 0.4 0.7
21,010,000 0.5 0.85
28,006,000 0.4 0.6
22,914,000 0.5 0.8
30,560,000 0.35 0.6
9-11
Wire
Size circular mils
26 AWG
24 AWG
23 AWG
22 AWG
20 AWG
19 AWG
18 AWG
16 AWG
14 AWG
12 AWG
4,110
6,530
10 AWG 10,380
8 AWG 16,510
6 AWG
4 AWG
2 AWG
1 AWG
26,240
41,740
66,360
83,690
250
400
510
640
1,020
1,280
1,620
2,580
1/0 AWG 105,600
2/0 AWG 133,100
3/0 AWG 167,800
4/0 AWG 211,600
350 kcmil 350,000
373 kcmil 373,700
500 kcmil 500,000
535 kcmil 535,500
750 kcmil 750,000
777 kcmil 777,700
Chapter 9
DC Power Distribution
Copper ampacity
60°C 75°C
55
70
95
110
15
20
30
40
3
4.2
7
10
0.8
1.3
1.5
2.3
65
85
115
130
50
150
175
200
230
310
380
475
Table 9-4 Power Wire Ampacities
15
25
30
40
55
75
85
Aluminum ampacity
60°C 75°C
50
65
90
100
20
30
40
120
135
155
180
250
310
385
PUB 77385
Issue K, July 2015
Aluminum
Ω /kft
0.7
0.44
0.28
0.22
0.17
0.14
0.11
0.086
0.052
11
7
4.5
2.8
1.8
1.1
0.037
0.024
Copper
Ω /kft
2.8
1.8
1.1
0.7
0.44
0.28
0.17
0.14
12.5
9.2
7
4.5
46
29
23
18
0.11
0.087
0.069
0.054
0.033
0.031
0.023
0.021
0.015
0.015
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Figure 9-9: Bus Bars run Flat
Chapter 9
DC Power Distribution
Figure 9-10: Vertically Run Bus Bars
9.3 Power Plant Distribution Characteristics
Protectors (fuses or circuit breakers) being fed from a converter plant or a ringing plant shall NOT exceed or equal the capacity of the plant. An example would be that a 2-
Ampere ringing generator shall not have a fuse larger than 1.33 Amperes to the using equipment.
Distribution fuses and circuit breakers for CenturyLink ™ equipment (not applicable to
CLECs) shall not be multipled (e.g., daisy-chained) between loads or equipment bays.
This means that a single fuse or breaker can’t feed two or more separate buses (unless the buses are bonded together by bus work and labeled as a single bus). Ringing distribution is exempted, as defined in Chapter 10. Feeds to DSX bays where the power feeds only LEDs are also exempted.
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DC Power Distribution
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Circuit breakers may be capable of being alarmed either in the tripped (known as midtrip or electrical trip alarm), or both the tripped and off positions (the off position is referred to as alarm on mechanical trip, so a breaker capable of alarming in both conditions is sometimes referred to as mechanical and electrical trip, while a breaker that alarms only in the tripped position is sometimes referred to as electrical trip only).
Breakers 100 Amps and larger should generally be both electrical and mechanical trip, while smaller breakers may be mid-trip only.
To design a distribution system, the following characteristics of a power plant must be determined:
• Plant voltage limits
• Protection requirements
• Capacity and size of charging equipment
• Ultimate current drain required of the plant
• Physical relationship of the plant components based on floor space configuration
• Grounding requirements
DC/DC converters that are placed for equipment isolation should be physically located in close proximity to the served equipment.
9.4 Cabling and Bus Bar
Cables or bus bar carry the current from the rectifiers to the batteries, from the batteries to the discharge panel, from the discharge panel to any converter plant or other distribution, and/or to the loads, and then back to the batteries and rectifiers in the grounded return lead(s). Whether cables or bus bars are used, each type of conductor must be capable of carrying current to or back from its loads without overheating or exceeding the voltage drop requirement.
DC circuits may be run from one RT cabinet to another cabinet within 20 feet (further if protected by DC TVSS). However, DC circuits should not be run from inside one building outside to another building or cabinet unless they are isolated from the building DC plant with an isolating DC-DC converter (the converter is optional for RT applications) and protected with a DC TVSS. For further lightning influence protection, the DC power wire can be run in metallic conduit (which should be done for physical protection reasons anyways for portions of the run that are not buried) that is only endbonded at one end (if grounding wires are run through metallic conduit, though, it must be end-bonded at both ends). The building or cabinet they are serving should also preferably be under the zone of lightning protection of the building from which the DC circuit is being supplied.
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Chapter 9
DC Power Distribution
Stranded copper wire used in AC and DC circuits operating at less than 600 Volts rms is primarily insulated with one or more of the following compounds: flame-retardant synthetic or mixed rubber, e.g., styrene butadiene rubber (SBR), ethylene propylene rubber (EPR/EPDM); chlorosulfonated polyethylene (CP); thermoplastic elastomer
(TPE); polyvinyl chloride (PVC); non-halogenated materials (e.g., polyethylene-co-vinyl acetate thermosets), or EPDM-CP composite structures. The chief compositional distinctions between insulation materials that lead to functional consequences for power cable products are whether these insulations contain either lead or sulfur.
Concerns about lead compounds arise from environmental regulations, pollution impacts, and high costs of landfill disposal. Elimination of lead coatings (such as traditional “tinning”) and lead-based stabilizers could result in copper corrosion, reduced electrical performance in humid and moist environments, and/or thermal degradation of insulation materials (although advances are being made in non-lead materials due to RoHS requirements). Sulfur compounds are often used to promote or form cross links within rubber thermoset materials. These cross linked materials are resistant to chemical and mechanical degradation as well as dimensional distortion at high temperatures. However, the sulfur can react with the copper and accelerate corrosion. Given these considerations as well as the cold flow properties of the insulation type, two major areas of distinction are made between power cable products:
• Sulfur-containing insulations and all other insulations
• Cables with a braided cotton covering (treated for flame retardancy) and those without this covering.
Depending on the specific application, one wire or several wires in parallel may be used, and for DC application, they will generally be placed on cable rack (some small circuits may be run in conduit, or attached to the outside of cable rack, or run on cable rack hangers).
The power wire types that are approved for use by CenturyLink ™ are THWN, THW, or
THHN for AC: and XHHW, RHW-LS, RHH, and TFFN with cotton braid for DC wiring in the racks. For 12 AWG and smaller wiring within a bay, although RHW, RHH or
XHHW is preferred, THWN, THHN, and TFFN may be used where protected from abrasion and coldflow at impingement points. TFFN without cotton braid may also be used in conduit or attached to the side of the rack (when attached to the side of the rack, it must be protected from abrasion and coldflow at points of impingement).
Single conductor, whether solid or stranded is usually called wire; whereas cable is generally an assembly of two or more conductors in a common insulating sheath.
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Chapter 9
DC Power Distribution
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Issue K, July 2015
Solid wire is sometimes used, especially in the smallest sizes; however, power cable is generally stranded. There are three primary types of stranded wire used. Class B stranding (per ASTM B8) is known as “Standard”. Typically flexible power wire used in telecommunications applications is finer/smaller Class I stranding (as defined by
ASTM B172). In some cases, even finer stranding is used in flexible wire, such as Class
K (per ASTM B174). Class K is sometimes referred to as diesel locomotive (DLO) cable
(although DLO can sometimes also be Class I stranding). DLO cable is actually an
RHH-RHW type of insulation. Class K is also sometimes referred to as “super-flex” or welding cable. Although not an official designation, welding cable is also sometimes referred to as Class W.
For insulations containing halogen (soft-rubber styles of RHH or RHW), with or without the cotton braid, the conductor must be copper and tinned. All power cables used near flooded lead-acid and Ni-Cd batteries must be tinned to provide extra protection to the strands from the acid (or alkaline) vapors that may be given off by the batteries.
Non-halogenated thermoset cross-linked wire (all XHHW and some types of RHW or
RHH) does not require a cotton braid or to be fiber wrapped at lacing points. Nor does it require tinning outside the power room (there are no halogenic or sulfuric compounds to attack the copper). The exception is for class I type wire, which must be tinned (since it is likely to be used in the power room, near the batteries).
DC cotton braid or XHHW wire colors shall be gray, green, black, or red. Green is for grounding, and while the other colors can be used on positive or negative leads, if the colors are different for positive and negative, the gray is preferred for the grounded return side (usually positive) in traditional gray and black power cable offices, while red and black are commonly used in traditional RUS offices.
To distinguish RHW or RHH without a cotton braid that must have fiber wrapping at tie and impingement points from RHW or RHH that does not need it at the tie points, the non-halogenated thermoset cross-linked RHW or RHH without a cotton braid may be marked from the manufacturer. The DC thermoset cross-linked RHW or RHH wire without a cotton braid may be gray marked with a blue or black tracer, black marked with a red or white tracer, and the green wire shall be marked with a yellow tracer.
Except for legacy RUS offices and those Prem locations where power wire is brought to us, red DC wire color is only allowed in in-bay wiring; in CLEC cages, bays, and drops provided by the CLEC; on wiring harnesses; and in circuits where 16 AWG or smaller wiring is used. Even then it is discouraged (in fact, the NEC ® , in locations covered by the NEC ® , does not allow red wire in DC systems except for those that are grounded on the negative side), and must be labeled at both ends for polarity when the wire belongs to CenturyLink ™ (except for the legacy RUS offices where the red and black are very common).
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Cables and bus bar must be copper. Cables must meet the requirements of Telcordia ®
GR-347 and ANSI/ATIS-0600017, or ANSI/ATIS-0600028. Ampacity shall be per
Tables 9-1 through 9-4. Cable ampacity shall be at the 75ºC rating for wire sizes of No.
1/0 AWG or larger, and at the 60ºC rating for wire sizes No. 1 AWG and smaller (unless all terminations and wires are Listed for a higher temperature, which is almost always the case in newer equipment). The Ampacity for bus bar is at 70 ºC All wire used in RT cabinets shall be rated for at least 75°C.
The minimum distance between the bus bars and any other object shall be in accordance with CenturyLink ™ Pub 77350. This includes hot, return, and grounding bus bars.
Cables from rectifiers to batteries, between battery stands, and from batteries to PBDs will be on a separate cable rack from all other cables when they are not protected by a battery disconnect. These cables are generally referred to as “un-fused” cables.
Cable rack "power cable brackets" mounted to the cable rack at eighteen inch intervals may be used for power cables fused (or breaker-protected) at less than 70 Amps, and equal to or smaller than 4/0 AWG, only when small quantities of cables are required.
Adhere to the stacking height limitations for brackets listed in Tech Pub 77350. The use of segregated cable racks for power and switchboard cable is the first choice of installation in larger sites to avoid noise being induced onto the DC cables from the switchboard cables. All power cables larger than 4/0 AWG, regardless of protector size should be run on dedicated fused power cable only cable racks (in NSD, power cables smaller than 6 AWG are not generally allowed on the racks). In small sites (such as huts), where separate power cable rack may not exist, segregation of power cable from switchboard cable on the only cable rack may be used if power cables can’t be run on brackets attached to the switchboard rack. The placement of any type of cable used for anything other than power on fused power cable only racks is strictly prohibited.
Dedicated fused power cable only cable racks shall not be equipped with screens, pans, or cable horns. T-intersections and/or 90 degree turns in the racks require corner brackets in order to maintain the minimum bending radius of larger size cables. All cabling on these racks shall be secured per Tech Pub 77350.
Power cables (Battery and Battery Return) on unsecured cable racks shall be closely coupled and paired securely together at 24 inch maximum intervals.
Primary DC distribution is defined as leads from the power plant to the BDFB (feeder conductors) or switch PDF, or directly to equipment bays. Secondary DC distribution is defined as power from the BDFB to the equipment bays (load conductors).
The cable between the Power Distribution Boards/Bays, Batteries, and Rectifiers should generally be of the flexible type. Drops into equipment bays 4/0 or larger should generally be of the flexible type. For entry into Power Boards the tap should be within
15 horizontal cable rack feet.
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All wire shall be Listed copper conductors, have an oxygen index (LOI) of 28% minimum, and a UL ® 94-V0 rating. (Wire used internal to the Power Plant bays, and the Power Plant manufacturers' recommendation for wires connected to the protection devices shall be exempted from the above rule.)
It is also a requirement in CenturyLink ™ that all cable rack located in the Power room or area be engineered and installed according to CenturyLink ™ Tech Pub 77351.
Armored power cable shall be no longer than 3 ft in length, except for vertical runs in manufacturer's equipment, and shall never be run on a cable rack with switchboard or other power cable. Insulation coated (liquid tight) armored power cable can be longer than 3 ft and shall be suspended beneath the power cable rack or run on a separate cable rack for power equipment applications only. When insulation coated armored power cable is suspended, it must be supported every two feet. Armored cable outside the power room must be placed in accordance with CenturyLink ™ Tech Pub 77351.
Cable temperature shall not exceed 115 degrees F in any horizontal cable rack. In addition, there shall be no instance where an equipment surface temperature exceeds
115 degrees F without a highly visible warning label. Cable temperature in the vertical riser within the bay to the overhead rack may exceed 115 degrees F. However, if the cable temperature in any vertical riser within a bay is going to exceed 125 degrees F, there will be a highly visible warning label.
If the battery return bus is used as the MGB in the ground window, the bar(s) and the interconnecting copper bus must be sized to meet the ultimate Power Plant ampacity.
See CenturyLink ™ Tech Pub 77355 for separation and sequencing of connections.
The battery return bus should be placed above the Power Boards (or internal to them in small toll load only plants) unless it cannot physically go there (or there are cable access issues). If it can’t go there, an attempt should be made to get it as close as possible, and in no case should the distance exceed 30 feet.
The battery feed and return bus bars (in the cases where they are both above the equipment rather than one or both being internal to the equipment bays) shall not be stacked. The hot and return bus bars shall be isolated on the cable rack and spaced a minimum of 1'6” from each other, per Figures 9-11 and 3-2. Exceptions are allowed for the battery return bus bar for a BDFB, for the main charge/discharge bus, battery return bus bar, battery stands (see section 3.9.4), and the ground window bars.
Battery and battery return bus bars must be labeled with the power plant potential
(-48V, +130V, -130V, +24V, -24V, etc.) for the hot bus, and as battery return. Labeling shall be per the requirements of CenturyLink ™ Technical Publication 77350. The battery return must not be labeled as a grounding bar, except when it is the MGB in the ground window (per CenturyLink ™ Technical Publication 77355).
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Cable Rack
Insulator
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1’ 6”
(-48V) (BAT RTN)
Busbar
Power Distribution Frame or Battery Stand
Figure 9-11: Typical Mounting of Bus Bar above PDFs and Battery Stands
9.5 Protectors and Cable Sizing
Since smaller capacity protectors will operate more quickly in the case of resistive faults, they should be sized as close to 125% of the List 2 drain or the CLEC power feed order (if the CLEC does not provide a List 2 drain) as practical (and generally should not be more than 200% of the ultimate expected List 2 drain [including failover current for A/B circuits] unless there is no standard fuse size between 125 and 200% - due to future long-term potential load growth, CLECs are exempt from the 200% maximum protector size recommendation). Protector selection also establishes the minimum allowable cable size. Cable sizes may be increased above the minimum to meet voltage drop requirements (and usually are for 24 and 48 VDC systems).
The discharge and distribution protectors must be engineered for each application and must have a current rating that will protect their cables. For example, a standard 1/0
AWG cable, which can carry 150 Amperes, should always be protected by a fuse or a circuit breaker no larger than 150 Amps.
The protector size should not be subsequently oversized if larger cables are furnished to meet the voltage drop requirements. Protectors should not be so close in size to peak loads that nuisance protector operation or overheating of the protector occurs.
These protector sizing rules do not apply to fuses or breakers which feed BDFBs from the primary PBDs (main Power Board). For rules on sizing of fuses and breakers that feed BDFBs, see Section 9.2.
Cable sizing for the battery charge cables (from battery bus bars to main chandelier or directly to the plant buses) should be based on the ampacity of the batteries at the four or eight hour rate to 1.86 Volts per lead-acid cell (unless a higher rate battery is used for
DSL backup; in which case that higher rate shall be used) or equivalent for other battery types. If the battery stand is a two string stand using only one battery string, it is recommended that cabling be sized as if there are two strings on the battery stand.
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It is also recommended that the feeder cable(s) from the PBD to the BDFB be sized to the full ampacity of the largest possible feeder fuse or breaker for that BDFB, (e.g., 600
Amperes) regardless of the present size of the breaker or fuse protecting the circuit.
Cables are sized in the following way. First, determine the appropriate cable path for power cables through the office following existing or new cable rack routes to determine the cable length. This length is determined by TOP TO TOP measurement.
Top to Top is from the top of the power bay to the top of the use equipment bay. Then, cable sizes should be selected to meet the requirements discussed herein, including applicable voltage drop and cable ampacity (cable ampacity is based on the List 2 drain). Care should be taken with feeds and protection to devices that have A & B inputs and are switching capable, as in the case of certain fuse distribution panels
(FDPs). In these cases, both A & B feeds need to be sized to handle both loads on either feed.
All fuses and circuit breakers must be Listed and rated for the available fault current.
All protection devices (fuses and circuit breakers) must be AC rated for AC circuits and
DC rated for DC circuits (some are rated for both, and that is acceptable as long as the voltage to which they are exposed does not exceed their rating for that particular type of electricity). The fuses must be color coded to prevent mixing. AC rated fuses include but are not limited to FRN-R and NON types. DC rated fuses include but are not limited to TPA, TPN, TPL, TPJ, TPS, GMT, and 70 types. GMT and 70-Type fuses are not only commonly used in DC circuits, but may also be used for ringing (since they are rated for both the AC and DC voltages in ringing circuits). TPN type fuses (or another equivalent DC-rated and Listed fuse from another manufacturers that fits the fuse holder) must be used on a going forward basis (new fuses) in existing DC applications that formerly used the FRN and NON (RK1 & RK5 rated) types (although those types have DC ratings, they were not truly designed for DC).
Renewable link and H type fuses are not acceptable for use on a going forward basis.
When a DC fuse requires an accompanying alarm/indicating/pilot fuse, the pilot fuse used should be of the size and type required by the fuse block manufacturer to avoid nuisance blowing of the fuse on under sizing and overheating of the bypass resistor on over sizing.
Circuit breakers shall be of the thermal-magnetic or magnetic type and shall be Listed.
They shall be trip-free types. Contacts shall not be able to be held closed during an overcurrent condition, by holding the lever in the closed position.
Circuit breakers must be DC rated for DC circuits and AC rated for AC circuits. They cannot be intermixed and must be clearly marked as either an AC or DC breaker (they may be marked as both, and that is acceptable as long as the voltage to which they are exposed does not exceed their rating for that particular type of electricity).
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Switches shall meet all the requirements of the applicable UL ® and ANSI Standards.
Ferrous materials shall not be used for current carrying parts.
9.6 DC System Fuse and Breaker Sources
There are various types of fuse and breaker sources. From the DC power plant, there may be up to three fuse or breaker panels between the plant and the equipment (see below), or the equipment shelves can be fed directly from a PBD or BDFB/BDCBB:
• Primary Sources located at the power plant (PBDs)
• Secondary Sources:
1.
Battery Distribution Circuit Breaker Boards (BDCBB)
2.
Battery Distribution Fuse Board (BDFB)
3.
Power Distribution Frames (PDF) in switches (they have various names)
4.
Coded frame fuse panels associated with specific equipment
5.
Older Fuse Bays (FB)
• Secondary/Tertiary Sources:
1.
Miscellaneous fuse panels at the top of individual bays
2.
Miscellaneous breaker panels at the top of individual bays
Note that there are varying types of fuse and breaker panels now that don’t fit quite neatly into either the BDFB, or the miscellaneous fuse panel category. These are sometimes known as “micro”-BDFBs, “mini”-BDFBs, or remote-switchable DC fuse/breaker panels. While traditional BDFBs take up a whole 7’ relay rack, and miscellaneous fuse panels take up 1 or 2 rack units (RUs), these non-traditional fuse/breaker panel sources typically take up 3-15 rack units.
What they are called is not nearly as important as their treatment from a voltage drop perspective per section 9.2 rules. Regardless of its name or size, any fuse/breaker panel that only serves its own bay and possibly an adjacent bay (on either or both sides) is treated as a “miscellaneous fuse panel” for voltage drop purposes. This means that voltage drop from this panel to the equipment shelves it serves is negligible enough so that voltage drop calculations are not necessary. The ampacity of the wire size used
(see Table 9-4) must still meet or exceed the fuse or breaker size.
However, if the micro-BDFB or other non-traditional fuse/breaker panel installed at the top of one bay serves bays/shelves further away than just the adjacent bay, then it must be treated and labeled (both in the field, and on the site drawings) differently from a voltage drop perspective. When this is the case, the normal 0.5 V loop drop (see Figure
9-6) from the BDFB (or 1.5 V from the PBD – see Figure 9-7) to the fuse/breaker panel in the bay must be split in half, as depicted in Figure 9-12, below:
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Figure 9-12: Splitting the Voltage Drop when a Top-of-Bay Fuse Panel Serves
Equipment More Than One Bay Away
Distribution leads leaving the bay almost always leave from the top. Incoming power leads to a bay also generally enter from the top of the bay. The exceptions to this are when the secondary fuse source is mounted on a raised floor, or when CenturyLink ™
Real Estate approves the drilling of the floor underneath a primary or secondary fuse source bay, in writing. CenturyLink ™ Real Estate is solely responsible for core drilling floors in a Central Office environment. No installation supplier or contractor (unless hired by CenturyLink ™ Real Estate) is authorized to perform the core drilling function.
Tag both ends of every power, power return, and ground lead as instructed in
CenturyLink ™ Technical Publication 77350, "Central Office Telecommunications
Equipment Installation, and Removal Guidelines”.
A separate battery return lead will be paired and sewn together or otherwise closely coupled with each distribution or source lead whenever possible.
• This "pairing" requirement does not apply to cabling between the power plant and batteries and/or primary distribution board, or the cable within a few feet of the return bus of a secondary distribution center — e.g. BDFB.
• It is not required for RTs/Prems where DC plant size does not exceed 100 A.
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• In cases of a remote ground window where served equipment with shared frame return (this is rare and generally limited to older equipment) is not on the same floor as a remote ground window, the battery feed leads do not have to be paired with the battery return leads all the way to the ground window. For the portion of the run where the battery feed and the battery return leads are not paired, the battery return lead shall be paired back on itself, (this includes going though the same cable hole). The total impedance of the battery feed and the total impedance of the battery return must be equal (i.e., the voltage drop must be divided equally between the battery feed and the battery return — 0.5 V one-way drop for both the feed and return). Refer to CenturyLink ™ Pub 77355 for ground window guidelines as required.
• Between the bays and/or battery stands, internal to the power plant, paired battery and return are preferred. However, unpaired leads are allowed internal to the power plant.
The battery return lead will be separate and isolated from the building ground.
Specifically, frame ground return for equipment power should not normally be allowed on new equipment. If a supplier chooses to combine the battery return with the building ground, the equipment must be:
• Electrically isolated from the floor and ceiling.
• A minimum of six feet from any other equipment.
Fuse panel vertical bus bar shall be used to interconnect the individual panels. All of the fuses connected to one supply lead must be in one group on each bay, but there may be several groups on one bay which are connected to different supply leads (A and/or
B supply). Under no conditions will the "A and B" sources be tied together at a fuse panel. Interbay bus bars are available if the fuses in one group require more than one bay.
Fuse reducers will not be used in "dead front" DC fuse panels or any AC panel. A
"dead front" panel is defined as a fuse block with a cover on it. Fuse reducers shall only be used on "open face" fuse panels. "Open face" is defined as fuse panels in which the fuses are on the front and external to the panel face. Double fuse reducing (using more than one pair of reducers) is not permitted.
All fuse and circuit breakers for power boards shall be numbered according to the
CenturyLink ™ standard configuration for that power plant (see Chapter 2).
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The largest output fuse or breaker to be mounted in a stand-alone CenturyLink™owned BDFB/BDCBB bay shall normally be 100 Amperes (up to 150 Amperes in special cases) in order to minimize cable congestion. Partial-bay BDFB/BDCBBs serving as top-of-bay miscellaneous fuse/breaker panels are exempt from this rule for high-power equipment bays because cable congestion would not be as great due to the limited number of fuse/breaker positions. Some BDFBs do not allow fuses/breakers up to 100 or 150 A, and some require spacing around the fuse or breaker for sizes larger than 60
Amps. Do not exceed the largest fuse size possible for that specific BDFB, and follow manufacturer guidelines for spare positions if necessary. Using larger fuse sizes that require sparing of surrounding positions for heat dissipation should be avoided in fuse panels because it’s too difficult to ensure that the “spared” spaces will never be used; however, fuse blocks and circuit breakers that physically take up two or more positions/poles (as long as the poles are ganged together, either internally or externally) can be used.
The largest output distribution cable size to be run within the BDFB/BDCBB shall be a
1/0 AWG (BDFB/BDCBB feeder wires are exempted).
Blank panels on the BDFB/BDCBB shall be used in the following locations:
• Top panel
• Bottom panel
• Between panels, where there is a potential difference of more than 140 V between the panels
• Unequipped positions (a guard may be placed over an unequipped position in a
BDCBB, or the entire BDCBB must have a cover or door if there are exposed, unequipped positions)
Fuses shall be assigned starting on the bottom panel of each group and from left to right when facing the front of the assembly. Fuse panels should be equipped from the bottom up in top fed BDFBs.
A BDFB/BDCBB located on one floor shall not be used to supply equipment located on another floor. Feeds from BDFBs to Collocators — Virtual or Physical CLECs — can be exempt from this rule.
For all new full-bay BDFB additions, configurations of battery return bus bar are encouraged to be mounted in the immediate area above the BDFB framework, (see figurers 9-9 and 9-10) in order to reduce cable congestion inside the BDFB/BDCBB.
This bus bar will provide termination for calculated battery return feeders from the power plant, and for the returns from the secondary distribution leaving the BDFB.
The battery return will be sized with up to 750 kcmil cable using the same engineering criteria as the power feeders for the BDFB.
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The maximum continuous drain on each feeder to a BDFB (or any A/B fuse/breaker panel) shall not normally exceed 40% of the protector (fuse or breaker) size for that
BDFB due to the increase in load current while on battery discharge, and shall never exceed 50%. For example, for a BDFB protected at four hundred (400) Amperes (load A or B) the maximum continuous drain for each load (A or B) should not normally exceed
160 Amps, and shall never exceed two hundred Amperes.
Each distribution fuse panel on the BDFB shall be labeled with the voltage and polarity of that panel. Each fuse position 01 through XX on each of the panels shall be labeled both front and back to indicate its' location. Each fuse panel shall be labeled to indicate the panel's position within the BDFB, 1, 2, 3, or A, B, C, etc. Typical arrangements are shown in Figures 9-13 through 9-16.
All fuse positions (in a vertical panel BDFB) smaller than 70 Amps should be installed and assigned from the bottom up to avoid cable congestion and for equipment reliability when an installer is adding future fuses. However, fuse position numbering is from the top down.
For any additional fuse panels added to the BDFB after the initial order, the panel position, voltage, and polarity shall be labeled by the installer.
The installer shall stamp the load designations on the fuse labels and the meter load designation label. Reference loads with alphabetic characters (A, B, C, D, etc.). Panels linked together with a bus bar will have the have the same load designation.
The battery feed and battery return cables shall be labeled on both ends using a designation tag to indicate the other end of the cable, per CenturyLink ™ Technical
Publication 77350.
The following sign should be placed on the BDFB. The sign should be visible and clear.
The size of the sign should be 3 inches by 4 inches.
All fuse positions should be installed from the bottom up to avoid cable congestion and for the safety of the installer adding future fuses.
Figure 9-13: BDFB Fuse Assignment Label
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All BDFBs should be installed and labeled as Figures 9-14 through 9-16 indicate.
-48 Volts
PNL # LOAD
01
02
03
04
05
06
07
08
15
16
17
18
19
20
09
10
11
12
13
14
11 11
12 12
13 13
14 14
15 15
16 16
17 17
18 18
19 19
20 20
01 01
02 02
03 03
04 04
05 05
06 06
07 07
08 08
09 09
10 10
15
16
17
18
19
20
09
10
11
12
13
14
-48 Volts
Fuse Blocks
PNL # LOAD
01
02
03
Panel number 1,2,3,etc
BDFB Load (A, B, C. etc.
04
05
06
07
08 Fuse Designation Card
Figure 9-14: Typical Layout of BDFB Fuse Panels
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Figure 9-15: Typical Layout of 2 Load 600 Ampere BDFB
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Figure 9-16: Typical Layout of 4 Load 400 Ampere BDFB
Battery return bus bars for the 7’-0” BDFB should be mounted using Figures 9-17 and
9-18 as typical. Nine foot or 11’6” BDFBs should be mounted per the CenturyLink ™
Engineer’s instructions, CenturyLink ™ standard configurations, and Technical
Publication 77351.
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Figure 9-17: Typical Return Bus Bar Mounting for a 7’ BDFB (View A-A)
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Figure 9-18: Typical Return Bus Bar Mounting for a 7’ BDFB (View B-B)
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No loads may be added to any BDFB that has been EMBARGOED.
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One or more of the following labels shall be on every BDFB:
The Maximum continuous drain on each feeder to this BDFB is ______ Amperes
The Maximum continuous drain on each
The Maximum continuous drain on each
As of __/__/__ this BDFB has been
EMBARGOED
for new growth due to load!
Figure 9-19: Load and Embargo Labels for BDFBs
Equipment shelves may receive their A and B feeds from separate power sources (e.g., two different BDFBs and/or PBDs) only when the power sources have a normal operating voltage differential of less than 0.3 V as measured at the equipment being fed, and only when the power sources ultimately use the same battery chemistry (e.g. flooded lead acid).
Fuse Bays (FBs) or miscellaneous fuse panels are designed to provide a centralized location for switching or IOF equipment to obtain power of small loads. The FBs are provided with power from a BDFB, Power Board, ringing plant, etc.
Input connections to miscellaneous fuse or breaker panels fed by a fuse or breaker greater than or equal to 50 Amps shall be two-hole lug design.
Older FBs were equipped from the bottom up with filtered supplies being located at the bottom and miscellaneous supplies directly above. Voltages increase toward the top of the bay.
Loads shall not be parallel fused (the same exact load position fed from more than one fuse or breaker). Parallel fusing violates NEC ® Article 240.8.
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A new BDFB/BDCBB should be added when any of the following occurs:
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• The existing BDFB/BDCBB has no remaining fuse positions on the A side, B side, or both
• The actual load on any one side (A or B) or panel of a BDFB/BDCBB exceeds 50% of the protector size feeding it
• The List 1 (average busy-hour, busy-season) drains of the served equipment exceed the capacity of the BDFB. The capacity is based on the rating of the upstream breaker or fuse. As an example, a BDFB panel fed by a 400 Ampere protection device has a nominal load limit of 200 Amperes on any one side (A or
B) so that their total load does not exceed the 400 Amperes fuse capacity. Every effort should be made to obtain the List 1 drains from the equipment suppliers in order to determine whether another BDFB is needed.
Any given secondary or tertiary protector in a fuse/breaker panel shall be smaller than its upstream primary/secondary protection device (it may be equal to it if it is faster responding). The engineering supplier is responsible for proper protector sizing and wiring them correctly (this is known as fuse coordination). Feeds to CLECs are exempt from this requirement. When a downstream fuse or breaker is part of a specific equipment shelf, no other fuses or breakers can be fed from the upstream fuse, and the equipment manufacturer allows a smaller upstream fuse or breaker to feed the shelf in their documentation, then that particular shelf may be exempt from fuse coordination.
When a fuse has blown or no fuse is inserted (or a breaker has tripped or is turned off), fuse/breaker positions/holders shall not have residual voltage bled to the outputs from fuse panel alarm circuitry.
9.7 Bus Bar Labeling and Layouts
The following bus bars should be installed, labeled and laid out in accordance with requirements herein, CenturyLink ™ Tech Pubs 77350, 77351, 77355; and standard configs (note that the positions of the bars is for illustrative example purposes only, and may be different in actual practice depending on the space and needs in the site.
48V BAT RTN
Figure 9-20: Example of Bus Bars (Term Bars) above a Battery Stand
Term bars above a battery stand are typically used for stands that will have more than one string. When there are stands with individual strings, they may often be cabled directly to the plant, or to the chandelier.
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BDFB XXX.XX RTN
Figure 9-21: A Battery Return Bus Bar above a BDFB
MTB –48V
Figure 9-22: Chandelier Hot Side Main Terminal (Term) Bar
Depending on the size of the plant, the hot side of the chandelier may be multiple bars.
In some cases no chandelier is used, and the batteries (and rectifiers when they are in separate bays) are cabled directly to the plant (PBD) hot buses.
(SHUNT)
XXX AMP
XX mV
BAT RTN CHARGE BAT RTN DISCHARGE
ONLY RECTIFIER &
BATTERY LEADS
BATTERY RETURN LEADS
(DISTRIBUTION RETURN
LEADS)
Figure 9-23: Chandelier Return Side Bars
There may also be a separate return bar over the PBDs (cabled to the discharge side of the chandelier), while the chandelier is typically located over the battery stands. In smaller plants, the return bar may even be internal.
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INTEGRATED
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CO GRD
CONNECTION
COGB
ISOLATED
Figure 9-24: Example of a Remote Ground Window
(SHUNT)
XXX AMP
XX mV
INTEGRATED BATTERY
RETURN LEADS
BAT RTN DISCHARGE
INTEGRATED
BAT RTN CHARGE
TO COGB
ONLY RECTIFIER &
BATTERY RETURN
LEADS
BAT RTN DISCHARGE
ISOLATED
ISOLATED BATTERY
RETURN LEADS
Figure 9-25: Example Main Return / Ground Window MGB Bar
The charge/discharge bar is often physically separated (but connected by cabling) from the return bar that is part of the isolated portion of the MGB.
Termination Lugs (top & bottom)
Bus Bar
Note : Sandwiching of the battery loads and returns at the bus bars for the
PBD, battery stands, ground window, and BDFBs is acceptable.
Whenever possible the loads and returns should be from the same equipment location. However, the placing of two or more termination lugs under one bolt on the same size of the bus bar (also know as stacking) is prohibited without exception.
Figure 9-26: Example of Sandwiched Terminations
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Chapter 10
Ring, Tone and Cadence Plants
CONTENTS
Chapter and Section Page
10. Ring, Tone and Cadence Plants .............................................................................. 10-1
10.1 General ............................................................................................................ 10-1
10.2 Ringing and Tone Systems Technical Requirements ............................... 10-1
10.3 Distribution .................................................................................................... 10-2
10.4 Ringing Plant Alarms and Troubles ........................................................... 10-3
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10. Ring, Tone and Cadence Plants
10.1 General
This unit is intended to provide general information regarding:
Chapter 10
Ring, Tone and Cadence Plants
• Ringing systems currently in use in switching and transmission systems;
• The various call progress tones furnished by ringing plants.
• General information on ring plant sizing.
In modern Class 5 switching, ringing, call procession tones, precision tones - Dual Tone
Multi-Frequency (DTMF), dial tone, audible ringing tone, high tone and low tone) are provided by the switch. A separate ring plant must be provided for all non-switched services such as Foreign Exchange (FX), ring down, Interexchange Carrier (IEC or IXC) special ringing requirements, metallic facility, DLC that doesn’t provide its own ring, etc. This section describes the requirements for that separate ringing plant. (All power equipment must have completed the CenturyLink ™ product selection procedure.)
10.2 Ringing and Tone Systems Technical Requirements
Ringing signal in CenturyLink ™ is 20 Hz (capable of supplying loads with power factors ranging from 0.8 leading to 0.5 lagging) ±1% (25 or 30 Hz settings are permissible for older circuits that need them). Call progress tones, such as dial and busy tones for the switched subscribers also need to be provided. In most cases, the equipment providing
POTS service (switch and/or DLC) provides both the ringing and the necessary tones either on the card, shelf, or bay. In other cases, it might provide the tones but not the ringing current. When either ringing current and/or tones are not provided by a piece of equipment but are necessary, they are supplied by a residual bulk ring plant (if tones aren’t needed, the plant doesn’t need to be equipped with that capability).
Where practical, the bulk residual ringing supply should be installed in close proximity to the circuits that need it. However, when those circuits are found all over the site, the residual ring plant is often located in the DC power room.
When bulk residual ringing or tone (sometimes provided by interrupters) supplies are provided, they must be provided in a redundant configuration. Transfer to the reserve unit may be accomplished by use of a manual transfer switch and automatically when the online supply fails.
The ringing equipment shall operate within an input voltage range of -44 to -56 VDC (or
-21.4 to -28 for nominal -24 VDC sites). The ungrounded supply lead(s) must be properly fused, and must have separate feeders for the regular and reserve units.
The input circuitry to any ringing generator shall consist of an input fuse and an input filter that prevents noise from being fed back from the generators to the batteries.
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The ringing equipment shall have built-in protection against undervoltage, overcurrent, and overvoltage on both the input and output.
The ringing generator output voltage level shall be regulated to a constant voltage level
(typically between 86 and 88 VAC superimposed on -48 or +48 VDC [AC/DC AUD], or nominal ±105 VAC for longer loops) within ±6%.
The wave shape of the ringing generator output must be low in harmonic content.
The efficiency of a ringing generator shall be high at light loads.
It is permissible to operate ringing generators in parallel, or in a primary-secondary configuration. Generator output power may also be increased by use of a booster.
It is permissible to use the same ringing generator for both battery and groundconnected trip circuits, provided that an isolation transformer is used.
Precise tone generators must have a frequency stability of ±0.5%, THD of 1% or less, and output voltage regulation to ±1.0 dB.
The Receiver Off Hook (ROH) generator shall be designed for fully automatic operation with permanent signal line systems. The 2600, 2450, and 2060 Hz frequencies of the
ROH generator shall be stable within ±2% over the input voltage range, and output load range from no load to full load. The 1400 Hz frequency shall be stable within ±0.5% over the same input and output voltage range. Harmonics in the output frequencies of the ROH generator shall be limited to a level of 26 dB down from the level of the fundamental frequencies.
All components of the ringing equipment shall be removable through front access. The ringing equipment shall be modular.
During growth/additions, delivery of power to the using systems shall be maintained.
All ringing equipment shall have a nameplate with a minimum of the supplier’s name, model and serial numbers, and manufacturing date.
Residual ring plants should be sized at a minimum of approximately 15 VA for every
100 circuits served.
Ring plants installed in controlled environments shall meet the temperature range requirements of Telcordia ® GR-63. Those designed to be used in RT cabinets must meet the temperature extremes of GR-3108.
10.3 Distribution
At least one distribution fuse shall be provided at a minimum. A primary or split fuse panel may also be used. The engineering supplier is responsible for proper fusing and sizing of ringing supply leads.
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Protection devices (fuses or circuit breakers) being fed from a ringing plant shall NOT exceed the capacity of the plant by more than 25 percent. An example would be that a
100 VA ring plant shall not have a fuse larger than 1.33 Amperes to protect the using equipment. Load fuses shall be smaller than the plant output fuse.
All distribution from SPCS ringing and tone frames to non-SPCS equipment must be run within three feet of the ground window and have the return lead bonded to the main ground bus. When a separate residual ringing supply is provided, all of these circuits must be moved to the separate supply, and the leads rerouted.
Ringing plant distribution fuses shall not be multipled (e.g., daisy-chained) between equipment bays for new feeds, although daisy chaining of ringing distribution within a bay is permissible.
All new ring plant distribution shall be dead front.
10.4 Ringing Plant Alarms and Troubles
Alarms are required for all office ringing supplies. Typical alarms required are major, minor, ring machine transfer, and interrupter transfer (when there are interrupters).
Alarm indications, such as major, minor, and transfer should be visual on the plant, with provisions for remote alarming (dry Form C or Form A contacts). All alarm points shall be easily accessible for connection to a PSMC.
During normal operation, if a trouble condition should occur in the regular 20 Hz ringing generator, tone generator, or the interrupter, the load shall transfer to the reserve unit after a 2 second time delay, but before the start of the next ringing cycle
(given that a typical ring cycle is 2 seconds on and 4 off, a transfer between 2-4 seconds is required). A trouble lamp(s) shall light to indicate trouble and an alarm signal(s) shall be activated. After the trouble has been cleared, that unit shall transfer back to normal operation by manual transfer only. In addition, all the associated alarm lamps shall be extinguished. If some element in the reserve side of the equipment fails without an earlier failure in the regular unit, a trouble lamp(s) shall light to indicate which output has failed, and an alarm(s) shall be activated.
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Chapter 11
Power Pedestals
CONTENTS
Chapter and Section Page
11. Power Pedestals ........................................................................................................ 11-1
11.1 General ........................................................................................................... 11-1
11.2 Materials ........................................................................................................ 11-2
11.3 Technical Requirements .............................................................................. 11-2
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11. Power Pedestals
Chapter 11
Power Pedestals
11.1 General
This unit covers power pedestals for use in the RT environment. The power pedestal is the interface between commercial AC, the standby AC connection (portable genset hookup), and the Outside Plant enclosure (e.g., CEV, RT, etc.). The pedestal is generally separate from the RTs at the site (this is the preference in order to clearly demarcate the responsibilities of the electrical inspector on the AC side), however, with approval of the local electric utility it may be mounted to the side of the RT for right-of-way (ROW) reasons only. The separate power pedestal also gives flexibility for future growth of
RTs and pedestals at the site without the need for another meter and power drop.
The power pedestal shall be designed to prevent personnel exposure to safety hazards.
The pedestal will be equipped with warning signs and guards, in agreement with UL ® requirements. The pedestal shall be Listed.
Due to right-of-way, roads, etc., it is not always possible to place a power pedestal next to the RT(s) it is serving. Although a power pedestal can theoretically be placed up to
1000 feet from the RT(s) it is serving, it is typically not economical to place the RT more than 150 feet from its power pedestal. A new location or an expanded ROW for the RT should be considered if this maximum 150-foot distance is exceeded. The distance rules for the power pedestal from the transformer are the same.
Each pedestal and/or framework shall have a visible nameplate with the following information: suppliers name, serial number, model number, manufacturing date, nominal input voltage(s), number of phases, rated frequency, the output voltage (if equipped with a transformer that makes it different from the input voltage, both must be Listed), the rated full load current, and the available interrupt current rating of the pedestal.
The interrupt current rating of the pedestal and its breakers must exceed the available fault current available from the serving utility company transformer.
The pedestal shall not have any openings sufficient to allow rodents, snakes, or other animals to enter and/or make their home inside the pedestal.
The pedestal shall meet the service requirements of any electric utility in CenturyLink ™ territory. In practical terms, this means that different models of pedestals must be provided for different areas.
Pedestals (and all AC services to CenturyLink ™ sites) should be equipped with
Transient Voltage Surge Suppression (TVSS). The suppression technology can be MOV,
SAD, or MOV/SAD hybrid designs. All TVSS units must be UL ® 1449 3 rd edition
Listed, tested to the appropriate ANSI/IEEE C62 series standard, and installed in compliance with Articles 280 and 285 of the NEC ® (this also applies to large site TVSS).
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Circuit breakers should have their interrupt current rating specified.
Input breakers for the commercial AC and portable genset must be of the walking beam interlock type transfer system.
Both ring and ringless type meter sockets are used, depending on the requirements of the serving electric utility. In some cases, a particular power pedestal model may come with a meter socket. In those cases where the pre-installed meter socket isn’t acceptable to the utility, the contracted electrician may remove it and replace it with one acceptable to the serving utility. In other cases, the power pedestal does not come with a meter socket. In those cases, the electrician must provide one acceptable to the local utility. In rare cases, the choice may be made to use non-metered service (when offered by the local electrical utility). This should generally be avoided (because it is usually not the least expensive option in the long run), and should only be used when the expected maximum load is small and will not grow much over the life of the overall site.
Some utilities require an external (or separately accessible) disconnect other than the meter socket itself.
11.3 Technical Requirements
The structural members of the power pedestal shall not carry or conduct load currents under normal operating circumstances.
All metal parts shall be grounded. Metal surfaces shall be bare metal at the points where they bolt together for bonding purposes or connect to the grounding system.
The pedestal shall be capable of being mounted in one or more of the following configurations: on a concrete pad (self-supporting), on a pole, or in a NEMA ® 1A type cabinet. In practical terms, these are usually separate models.
Service entrance conductors shall be run only in conduit, and the pedestal shall be capable of overhead or underground entrance. If entrance is through the bottom of the enclosure, the supplier must provide a vented dead air space. No equipment shall be mounted in this area. The space must be a minimum of four and one half inches in depth. The load conductors shall be run only underground, and in conduit.
The enclosure shall be lockable.
The enclosure shall be equipped with either a hinged door opening to a minimum of
160 degrees, or a removable front cover.
The commercial AC feed must not be accessible to the public from the meter back towards the source. While most power pedestals have internal risers for the electric utility feeds to the meter socket, some utilities require these to be in a separate compartment (lockable by them), or external to the power pedestal.
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The load center (breaker panel) must have a minimum of six (and preferably at least twelve) positions, pre-equipped with one 15-Ampere breaker to be wired to a GFCI receptacle. The GFCI receptacle will be mounted in the enclosure. Because the power pedestal has a load center, there is generally no reason (and in fact, it is uneconomical to do so, and violates the principle of keeping the AC demarcation in the separate power pedestal) to have a load center in the RT as well, unless required by the local electrical inspector or utility. The RT generally has an AC junction box instead.
Visual alarm and status indications shall be provided by colored, illuminated devices mounted directly on the power pedestal. A dedicated overcurrent device operating from the plant voltage should be provided to power the visual alarms in the subsystem that indicate that the power to the status indication and alarm overcurrent devices have operated, or that power has been removed from the status indication and alarm/control system. The device can be either a fuse or breaker in the ungrounded supply lead.
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Chapter 12
Lighting (Emergency/Task)
CONTENTS
Chapter and Section Page
12. Lighting ..................................................................................................................... 12-1
12.1 Emergency ..................................................................................................... 12-1
12.2 Task ................................................................................................................ 12-1
Tables
12-1 Wire and Protector Sizing for -48 VDC Powered Lighting Circuits .................. 12-2
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12. Lighting
Chapter 12
Lighting (Emergency/Task)
12.1 Emergency
Emergency lighting (also sometimes called stumble lighting) is required by the NEC ® and Life Safety Codes (it must come on within 10 seconds of a power outage and last for
90 minutes) for egress from a building (stairwell lighting, main aisle lighting, exit signs, etc.). (Illumination levels and other detailed information can be found in NFPA ® 101 and in NEC ® Article 700.) It should be run off a contactor or sensor, or left on all of the time. This egress lighting is most reliable if -48 VDC powered, but the installation of this type of lighting is the ultimate responsibility of the CenturyLink ™ Real Estate department.
Battery pack lights are sometimes used for emergency egress lighting, but are not the best choice, especially when their batteries are not maintained. The most reliable choice for emergency lighting is -48 VDC powered fluorescent ballasts. The second-most reliable choice is AC lighting fed by an inverter powered from a -48 VDC plant. A third choice could be "emergency/egress" ballasts with a built-in battery. Wall-mounted,
”frog eye” style lights are the fourth common type of emergency egress lighting system.
DC emergency and stumble light fixtures shall be labeled to preclude use of the wrong bulbs and/or ballasts.
12.2 Task
Task lighting is not code required, but is required by CenturyLink ™ for the following locations when the main building is larger than 500 square feet:
• Engine Room (task lights are not required for outdoor engine enclosures)
• Transfer System Switchgear
• Indoor Engine Control Panel
• Indoor AC Service Entrance
• Main DC Power Boards (especially above the controller)
This lighting is best if it can be run on a switched circuit with a contactor or sensor that will light it up during an AC outage even if the switch is off. Other options are running off a standard light switch, or on continually.
The following methods can be used to provide this lighting:
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Incandescent bulbs shall be -48 VDC types. These older systems cannot usually be maintained due to the fact that the bulbs are no longer made and are very difficult to find. There are both right and left-handed thread -48 VDC incandescent bulbs and fixtures. Also used were positive or negative 130 VDC fixtures and bulbs (standard 120
VAC bulbs can be used in these systems, but system labeling for these and for righthanded thread -48 VDC incandescent systems is critical so that maintenance personnel know whether they are dealing with an AC or DC system). These incandescent systems typically use a contactor that takes a non-essential AC source to hold the contacts open, but allow DC to flow when the AC is off. These systems should be replaced with fluorescent fixtures at the next convenient opportunity.
Fluorescent ballasts for task lighting shall be -48 VDC types (as noted previously, these same ballasts could also be used for emergency/egress lighting). They can be used in existing fixtures with existing bulbs. There are -48VDC input fluorescent ballasts that can be used in an always-on configuration, or in a switched circuit. Note however, that with these ballasts in a switched circuit, they will not automatically re-power the lights in an AC Fail condition if the switch is turned off. In addition, there are -48VDC inverter “ballasts” that do not power the tubes directly, but are instead wired in parallel with an AC input fluorescent ballast. If wired correctly, these can be used in a switched circuit that will automatically power/light the fixture in the event of an AC failure, regardless of whether the switch is "off or on".
DC lighting can be fed from the nearest -48 VDC source (main Power Board, BDFB, or even miscellaneous fuse panels). If feeding from the main Power Board or BDFB, it is permissible to run several fixtures in parallel off a single circuit (similar to AC lighting), following the provisions of the NEC.
Because of the low power drain of DC lighting fixture ballasts (1-2 Amps of -48 VDC current per fixture), and since we use the nearest DC source, and the minimum voltage of the bulbs or ballasts is typically 30 VDC, voltage drop will not normally be an issue.
The following wire and fuse or circuit breaker sizing guidelines might generally apply for -48 VDC lighting circuits.
Table 12-1 Wire and Protector Sizing for -48 VDC Lighting Circuits
Number of
Fixtures
1
2-3
4-5
6-7
8-10
Minimum
Wire size (AWG)
14
14
14
12
10
Protection Device
Size (Amperes)
5-15
10-15
15
20
30
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Any circuit feeding more than three fixtures should be fed from a BDFB or main Power
Board, not a miscellaneous fuse panel.
Although not required, these DC lighting circuits would generally be run in conduit.
This conduit cannot contain any AC circuit wires. The DC wires cannot be white, red, blue, brown, orange, or yellow. This will generally prevent accidental connection at junction boxes to the AC system. A green wire ground shall also be run, in accordance with the NEC, and tied down to the ballast and/or bonded to any metallic fixture case it feeds. Back at the fuse source, the green wire ground can then be tied to the frame.
Any conduit must be metallically bonded back to ground too, either with a bond to the green wire at the fixture case, or at the junction box, etc. The size of this ground wire does not need to be any larger than the largest -48 VDC or return conductor run in the conduit.
If the site has a power inverter with spare capacity, regular AC lighting can be provided from it (this is actually preferred because traditional AC ballasts last longer than DC ones). It can be switched or permanently on, or on a contactor, depending on whether it is emergency or task lighting (task lighting is best if switched for energy and longevity purposes). (Each fixture uses 75-100 W/VA of inverter load.) The fixture shall have a label visible from the floor identifying it as inverter fed.
If you have a site that has multiple engines in parallel, task lighting (but not emergency egress or stumble lighting) can be from the essential AC bus fed by these paralleled engines.
Standard low-level equipment lighting arrangements shall be installed per
CenturyLink ™ Technical Publication 77351 and CenturyLink ™ Standard Configuration documents.
For external engine enclosures, task lighting (if provided at all) can be powered off of the engine start battery circuit only if it is on a timer switch so that it does not drain the battery. DC leads should not be run from the building to perform this function or to provide emergency egress lighting for a walk-in enclosure due to the risk of bringing lightning back into the DC plant. Inverter powered lighting is an option for outdoor engine enclosures for egress and/or task lighting, but the circuit must have a TVSS device at the point it enters/leaves the main building.
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Chapter 13
Standard Alarm Messages and Thresholds for Power
CONTENTS
Chapter and Section Page
13. Standard Alarm Messages and Threshold Settings for Power .......................... 13-1
13.1 General ........................................................................................................... 13-1
13.2 Power Alarm Standard Messages Reporting to NMA ® ......................... 13-2
13.3 TL1 Query Messages for Power ............................................................... 13-30
13.4 Set Points (Thresholds) for Power Alarms and Power Routines ........ 13-32
13.5 Typical Power Alarm and Monitor Points ............................................. 13-42
13.6 Power SNMP Traps ................................................................................... 13-44
Tables
13-1 AID for Power Alarms ............................................................................................. 13-5
13-2 Power Alarm Condition Types ............................................................................... 13-9
13-3 Reduced Character and Overhead Bitstream TL1 Alarm Condition Types .. 13-14
13-4 DMS ™ 10 Pre-Assigned Scan Point Messages for Power Plants ....................... 13-15
13-5 DMS ™ User-Assignable Scan Point Power Standards for NMA ® .................... 13-17
13-6 Power Messages for Integrated DMS ™ -1 Urban ................................................. 13-20
13-7 NMA ® Power Messages for Nortel Remote Switches in RTs ........................... 13-22
13-8 5ESS ™ Standard Power Messages for Hosts ....................................................... 13-23
13-9 5ESS ™ Standard Power Messages for Remotes .................................................. 13-24
13-10 5ESS ™ User-Assignable Scan Point Power Message Standards ....................... 13-24
13-11 Ericsson AXE ™ Standard Power Alarm Messages for NMA ® .......................... 13-27
13-12 TL1 Query Messages for Power ............................................................................ 13-31
13-13 Typical Output Voltage Settings ........................................................................... 13-33
13-14 Battery Plant Voltage Alarm Set Points ............................................................... 13-35
13-15 Converter Plant (no batteries on output) Voltage Alarm Set Points ............... 13-36
13-16 VRLA Temperature Compensation and Recharge Current Limit Settings .... 13-37
13-17 Power Temperature Alarm Set Points ................................................................. 13-38
13-18 Current Thresholds ................................................................................................. 13-39
13-19 Battery Ohmic Thresholds ..................................................................................... 13-40
13-20 AC Voltage Thresholds .......................................................................................... 13-41
13-21 Fuel Alarm Thresholds ........................................................................................... 13-41
13-22 kW/kVA or AC Load Current Capacity Thresholds ........................................ 13-42
13-23 Typical Power Alarm Points for Smaller Sites Without Engines ..................... 13-42
13-24 Typical Power Alarms for Small Sites with Only 4 Overhead Bits ................. 13-43
13-25 Typical Power Alarms for Small Sites with Only 2 Overhead Bits ................. 13-43
13-26 Power Points for Larger Sites with Engines ........................................................ 13-43
13-27 SNMP Power Alarm Messages used in CenturyLink ™ ..................................... 13-45
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13. Standard Alarm Messages and Threshold Settings for Power
Chapter 13
Standard Alarm Messages and Thresholds for Power
13.1 General
This chapter contains CenturyLink ™ standard Power messages in PSMCs, using X.25 or
IP packet protocol with TL1 language. Also included are standard names for alarms connected to e-tel devices, whether those alarms use E2A or IP protocol for backhaul.
Naming conventions for housekeeping alarms connected to the overhead bits of fiber muxes and other network equipment are also included. Naming standards for power alarms hooked to switch scan points (whether they report to NMA ® , or eventually to an
SNMP alarm management system) are also given. Finally, naming standards are given for approved MIBs (Management Information Bases) for alarms reporting directly to an
SNMP management system. Standard MIB SNMP trap messages for alarms reporting to NMA ® for translation to TL1 via a template may be added in the future.
There are several parts to this chapter. Section 13.2 explains the use of the AID and
Condition Type fields in PSMCs that report their alarms directly to NMA ® . These same
AIDS and Condition Types, along with a few other messages, are also programmed in
NMA against binary points that are polled or transmit to NMA from an e-telemetry device. Standard switch scan point power alarm mnemonics, along with the corresponding NMA TL1-traslation messages are also given. Section 13.3 defines the
TL1 queries that may be performed on X.25 and IP-compatible Power System
Monitor/Controllers (PSMCs) to extract useful information from them. In the future, this section may also include useful power-related SNMP GET messages. Section 13.4 defines the threshold settings for binary power alarms derived from analog readings.
Section 13.5 provide a few examples of typical standard power messages. Section 13.6 covers some of the standard power messages found in CenturyLink ™ SNMP networks.
Power and environmental alarms make their way to NMA ® or to an SNMP alarm management system over one of several different transmission media. These media are listed below in order of preference. Alarms should not be sent through more than one of these mediums (except for backup generic majors and minors) due to the confusion multiple alarming causes for the surveillance technicians. Preference is based on the ease of routing and/or analysis allowed by the particular media.
• TL1 on an X.25 or IP circuit from a Power Monitor (PSMC) with backup major, minor and watchdog alarms through an e-telemetry or switch medium
(environmental alarms should not generally use a PSMC, except for those specifically related to power, such as a battery room temperature)
• E-telemetry, or similar modern alarm systems that report e-telemetry (binary alarms) via an IP circuit, or via E2A polling
• X.25 overhead bitstream from Remote Terminal (RT) locations (including
Customer Premises)
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• SNMP Traps directly to an SNMP alarm management network loaded with the appropriate MIB that has been tested to work properly by the appropriate
CenturyLink ™ lab
• Through the switch scan points
Binary alarms connected to any of the above devices may be connected as closed on alarm (NO), or open on alarm (NC). Either configuration is acceptable for power and environmental alarms.
Most alarms are typically set up as closed on alarm (NO). However, critical alarms should probably be connected to open on alarm (NC). This setup (of alarming on an open condition) is also known as “guarded”. This refers to the fact that if the wiring is inadvertently cut or disconnected, or contacts get dirty, an alarm will be brought in. If alarms are connected in the “guarded” state, it is preferable that the reversal of the point be done on the alarm-monitoring device rather than in the alarm management system (such as NMA ® ). If the reversal is done in the alarm management system, it can cause problems for both field and center technicians by causing red lights, or bit sets
(which normally mean alarmed conditions to these technicians) when there actually is no alarm.
13.2 Power Alarm Standard Messages Reporting to NMA ®
Power alarms report to NMA ® via one of the following methods:
• As an X.25 or IP packet in TL1 language coming from a power monitor; or via the overhead bitstream as an environmental/housekeeping bit connected to a fiber mux, or other Network transport or access element. Portions of the full alarm message are programmed locally (or can be done remotely for many
Network elements via their software or via NMA ® ), usually including at least the SID (the network element System IDentifier, also known as a TID or Target
IDentifier when NMA ® is sending a message to the network element), the AID
(Access Identifier), and the Condition Type. A partially matching template/messaging is built in the NMA ® host computer, and portions of the message sent (including the SID and AID) must match the template in NMA.
• As a binary point connected to an e-telemetry device and polled from the NMA host computer via E2A protocol, or sent to the NMA host via IP packet. All of the messaging for these alarms is programmed point-by-point in the NMA host computer by the appropriate CenturyLink ™ NMA ® Database group in contact with a site technician who identifies exactly what the alarm is. These Power alarms may be either “Equipment” type, or “Miscellaneous” type, depending on which legacy CenturyLink company the site originally was.
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• As raw switch messages that originate when an external switch scan point changes binary state. Some of the switch scan points in some switch types are pre-assigned certain messages, while others are user-programmable with text field lengths of varying characters. When the raw switch message reaches
NMA ® , it is run through a script. If the message matches a value in the power alarm script, a “dynamic unit” and “TL1 condition type” are assigned and forwarded to the proper ticket creation scripts and worklist(s) in NMA ® .
The AID provides a "gross" definition of the equipment involved. An "n" associated with an AID indicates more than one entity of that type. The "n" will always be a number.
The second column in the AID table (normally called the sub-AID) on the following pages provides a detailed identification of the hardware involved in the message.
Every message will use the first column. However, the second column (or condition type) will not be used for every alarm condition. An "m" associated with the second column indicates more than one entity of that type. The second column may or may not have an associated "m". The "m" may be numeric, alpha, or alphanumeric. For those messages with the "m", it does not have to be there (this is especially true for generic plant alarms, such as a plant rectifier fail alarm).
In e-telemetry devices reporting to NMA ® , the unit shelf (for equipment type alarm databasing) or miscellaneous unit (for miscellaneous type alarm databasing) uses the same messaging standards as the AID and sub-AID.
As examples of messages, N48B1RECT4 refers to rectifier 4 in the negative 48-Volt battery plant #1; and N48B1RECT would be the overall AID for the generic plant rectifier alarm.
CONDITION TYPE (CONDTYPE) uniquely defines the condition or trouble to be provided to NMA ® from the alarm reporting device, or to be programmed into NMA ® for the e-tel devices. The CONDTYPE field is completely independent of the AID field, and for TL1 messages originating in a remote intelligent Network Element (NE),
NMA® will take whatever is sent to it by the NE (no matching database for the
CONDTYPE needs to exist in the NMA host computer).
NEs reporting TL1 messages are databased in NMA ® as equipment or environmental type alarms. Unlike miscellaneous type databasing, an extra field exists, known as the relay rack (RR). For power monitors or fiber muxes, this field is populated with the relay rack location of the monitor or mux when the NMA template programming is done, and that will be the location shown on the NMA alarm ticket regardless of where the actual alarm occurs in the site. For e-tel equipment type databasing, the actual location of the originating alarm can be programmed into the NMA ® host on a point-bypoint basis.
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In order to obtain a full description of the problem associated with a particular NMA ® message, the AID and CONDTYPE must be provided. For example, a CONDTYPE of
FAIL associated with an AID of N48B1RECT4 would indicate that rectifier 4 in the negative 48-Volt battery plant #1 failed.
N48B1RECT4 FAIL
Alarms are classified as minor (MN), major (MJ), and critical (CR) depending on the criticality of the alarm, and the time allowed before action must be taken. NMA® also has designations of SA (service-affecting) and NSA (non-service-affecting), which don’t really apply as well to power alarms as they do to other types of equipment; so by definition, major and critical power alarms are assigned the SA designation, and minor power alarms are assigned the NSA designation.
For power monitors capable of TL1 over X.25 or IP, a generic TL1 template should be generated in NMA ® against the monitor at a site (the TID of the monitor). This template generates numerous NMA ® AID entities for that TID, as well as the Equipment Type field that appears on the NMA ticket. If the AIDs programmed into the monitor match the AID entities of the template that is generated against the TID no more NMA ® programming needs to be done. However, each alarm must still be tested to ensure electrical and database continuity, as it is impossible to make the template large enough to include every possible power alarm. So, if an alarm is tested after the template is generated, and a ticket is not created, a specific entity for that alarm must be created, or the AID in the monitor must be changed to match one of the template AIDs.
Some smaller monitors aren’t capable of holding all the characters found in Condition
Type Table 13-2. Some fiber muxes, that carry power and environmental alarm messages on their overhead bitstream, can have as few as 10 characters for the TL1 condition type (often referred to in manufacturer or Telcordia ® documentation as the
ALMTYPE). This TL1 condition type for these messages must totally describe the event with the 10-characters. Most muxes also have a miscellaneous minimum 40-character field that can be seen by browsing the mux or sending a RTRV-ATTR-ENV or
RTRV-ALM-ENV TL1 command. The shortened messages shown in Table 13-3 may be used in place of the messages of Table 13-2. If a condition type is not found in
Table 13-3, that means the message of Table 13-2 is short enough. In some muxes, the
ALMTYPE is limited to the standard Telcordia ® set (those where the description is in quotation marks in Table 13-3).
Note that some “alarms” are really more status indications that help in alarm analysis and record-keeping, but don’t necessarily require dispatch. Examples might include a transfer switch proper operation, an engine run, etc.
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Chapter 13
Standard Alarm Messages and Thresholds for Power
Table 13-1 AID for Power Alarms (page 1 of 5)
Eqpt or
Misc Type power-plant
DC CONTROLLER
ENV
BATT
DCVLTG
LWBATT
BATDIS
RR
AID + sub-AID or e-tel Unit/Shelf or Misc Unit
BATTERY PLANT (page 1 of 2)
P130Bn
N130Bn
N48Bn
P24Bn
N24Bn
PSMCn
COM
LVD
ALARM m
DCMINOR
DCMAJOR
EQUAL
N/A HIVSHUT
HIFLOAT
RECTHIFLOAT
HIVOLT
ROOM
RPMm
SHUNTm
MPROC
Description positive 130 Volt battery plant #n negative 130 Volt battery plant #n negative 48 Volt battery plant #n positive 24 Volt battery plant #n negative 24 Volt battery plant #n power systems monitor/controller internal PSMC message low voltage disconnect unit or contactor ambient power room temperature remote monitoring module for a PSMC shunt or sub-shunt "m", or shunt-monitoring board power plant controller fail
DC plant generic minor alarm
DC plant generic major alarm batteries on equalize high voltage shutdown high DC plant voltage
VLTG high DC plant voltage or high/low voltage high or low DC plant voltage m
ALARM
ENV N/A
LOWFLOAT
LOWVOLT
BATDIS
RECTBATDIS
LWVDSCHG
RECTVLV batteries on discharge or low float voltage very low voltage at the DC plant
13-5
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Standard Alarm Messages and Thresholds for Power
Table 13-1 AID for Power Alarms (page 2 of 5)
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Eqpt or
Misc Type
RR
AID + sub-AID or e-tel Unit/Shelf or Misc Unit
BATTERY PLANT (page 2 of 2)
BATTFUSE ALARM m
P130Bn
N130Bn
N48Bn
P24Bn
N24Bn power-bat power-fuse power-rect
AC CHARGER ALARM m
RECTMJ
RECTFL
ENV
POWER BOARD
N/A RECTPHSE
CHARGER
RECTMN
ALARM FUSE
ENV
BDFB
POWER PANEL
ENV
N/A
RECTPRI
DISFUSE
CRCTBRK
DCFAIL
BDFBFUSE
ALARM m
N/A
LWVDISCO
BATDISC
FUSE
BATmLO
BATLIm
BATm
BATmM
BATmPC
BATmUP
LVD
BATCOMP
BMS
ABS
CNTRLm
DISTm
RECTm battery string fused disconnect open positive 130 Volt battery plant #n negative 130 Volt battery plant #n negative 48 Volt battery plant #n positive 24 Volt battery plant #n negative 24 Volt battery plant #n a cell in the lower tier of battery string "m"
Li-based battery battery string "m" battery midpoint voltage for string "m" pilot cell in string "m" a cell in the upper tier of battery string "m" battery low voltage disconnect temperature compensation active battery management system device fuse feeding alarm relays control fuse, breaker or relay "m" distribution (discharge) fuse/breaker "m" rectifier multiple rectifiers input phase to a rectifier rectifier "m" primary power plant distribution fuse blown tripped breaker secondary or tertiary distribution fuse alarm low voltage disconnect battery disconnected
Description
Collocation DC power input failure secondary distribution fuse or breaker
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Eqpt or
Misc Type power-ac
AC SURGE AC environ
N/A
ENV
POWER AC
ENV power-ups
UPS-
ENV
RR powerinverter
INVERTER ALARM
N/A
ALARM
N/A
Chapter 13
Standard Alarm Messages and Thresholds for Power
Table 13-1 AID for Power Alarms (page 3 of 5)
AID + sub-AID or e-tel Unit/Shelf or Misc Unit
1PHUPSn
3PHUPSn m
UPSNORM
UPSONGEN
UPSONBP
UPSBPNA
UPSNR
UPSBATT
UPSLOWBAT
UPSSHUT
UPSSUM
UPS
COMMERCIAL OR STANDBY AC
COMACn commercial AC service entrance #n
ACINn
CURNTm essential AC measured on load side of xfr switch n input or output AC phase "m" current
KWm
PHASEm
TRNSWm
VOLTm power produced by phase “m”, or total power
AC phase input AC transfer switch "m" input AC phase "m" voltage
ROOM
LIGHTN
LIGHTNING
TVSS FAIL
AC surge arrestor lightning detector disconnected AC & MGN
AC surge arrestor
COMMFAIL
FAIL commercial AC power failure
1PHINVn
3PHINVn m
INVERTGN
INVERTER
INVERTEROF
INVERTBR
INVERTLL
INVERTEROBP
INVERTBP
INVERTER PLANT single-phase inverter plant #n
TRNSW
DIST
3-phase inverter plant #n transfer switch in _-phase inverter #n distribution fuse/breaker for _-phase inverter #n any inverter alarm inverter general trouble inverter fail inverter output fail inverter breaker tripped inverter line loss inverter on bypass inverter bypass not available
UPS
BATCHGm
BATm
EPO
INVm
TRNSWm
Description of AID single-phase UPS plant #n
3-phase UPS plant #n battery charger "m" in _-phase UPS #n battery string "m" in _-phase UPS #n emergency power off switch/button activated inverter "m" in _-phase UPS #n transfer switch "m" in _-phase UPS #n
UPS alarm
UPS operating properly (not a transmitted alarm)
UPS being fed by engine-alternator(s)
UPS in bypass mode
UPS bypass not available loss of UPS redundancy
UPS on battery very low UPS battery voltage
UPS failure generic UPS summary/trouble alarm
13-7
Chapter 13
Standard Alarm Messages and Thresholds for Power
Table 13-1 AID for Power Alarms (page 4 of 5)
Eqpt or
Misc Type
RR power-engalt
GEN XFER RUN
EMERGENCY GEN ALARM
GEN FAILED
ENV N/A
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AID + sub-AID or e-tel Unit/Shelf or Misc Unit
Description of AID
STANDBY ENGINE-ALTERNATORS
ENGALTn stand-by engine/alternator #n
FUELPRES
BATCHG fuel pressure start battery charger for standby engine #n
BATENGm
COOLANT
CURNTm
DAYFUEL
FAN
KWm start battery string "m" for standby engine #n standby engine coolant input AC phase "m" current day tank of standby engine #n fan for standby engine #n power produced by phase “m”, or total engine kW
MAINFUEL main fuel tank of standby engine #n
OIL oil level or temperature m
OILPRESS
PHASEm
ROOM
TRNSWm
VOLTm
FAIL oil pressure for standby engine #n
AC phase from engine/alternator ambient engine room temperature transfer switch "m" operated optionally used for engine failure engine output AC phase "m" voltage engine run and/or transfer switch proper operation generic engine major alarm engine run RUN
MJ
GENFAIL
GEN RUN
GENLOAD
ATSTRAN
ATSEME
GENTR
GENLOWCOOL
GENCOOL
GENLOCOTMP
GENHICOOL
GENOIL
GENOVER
GENREV
GENPHSE standby engine failed engine running load transferred to engine engine-alternator trouble engine fail due to low coolant level engine coolant heater failure engine fail due to low coolant temperature engine fail due to high coolant temperature engine shutdown due to low oil pressure engine shutdown due to overspeed engine-alternator being back-fed (acting as motor) alternator output phase problem
GENSGF
GENCRNK
GENBATT
GENFUEL
GENDTLOW
TANK
FUELLEAK
GENAUTO
GENPARA
OILLEAK alternator breaker opened due to a ground fault engine start battery charger fail engine start battery low voltage main tank low fuel alarm day tank low fuel alarm tank fuel leak alarm generic fuel leak alarm engine controls or transfer switch not in auto engine(s) failed to parallel engine oil leak detected
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Chapter 13
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Table 13-1 AID for Power Alarms (page 5 of 5)
Eqpt or
Misc Type power-ring plt power-ringer power-inter
RINGING GEN
RING GEN INTER ALARM
RING GEN DIST
ENV power-cnvrter
CONVERTER
130V CONVERTER
ALARM
RR
N/A
RNGn m
AID + sub-AID or e-tel Unit/Shelf or Misc Unit
Description of AID
RING PLANTS
FUSEm
RGENm
INTERm ringing generator (plant) #n ringing generator fuse "m" ringing generator "m" in ring plant #n ringing interrupter "m" in ring plant #n ring plant alarm ring plant interrupter alarm ring plant distribution fuse alarm
RING
RINGTR ring plant trouble
P130Cn
N130Cn
PN130Cn
P48Cn
N48Cn
P24Cn
N24Cn m
CONVERTER PLANT positive 130 Volt converter plant #n negative 130 Volt converter plant #n
ABS positive & negative 130 Volt converter plant #n positive 48 Volt converter plant #n negative 48 Volt converter plant #n positive 24 Volt converter plant #n negative 24 Volt converter plant #n fuse feeding alarm relays
CONVm
DIST converter "m" in plant #n distribution fuse/breaker for plant #n
DC-DC converter plant alarm
130 V converter fail, or output fuse blown
Table 13-2 Power Alarm Condition Types (page 1 of 5)
CONDTYPE
ALARM_CUTOFF
ATS ON EMERGENCY
ATS LOAD TRANSFER
GENERATOR TAKING LOAD
BATTERY ON DISCHARGE
DISCHARGE
BATTERY ON DISCONNECT
CR, MJ, or
MN
MN
MN
MJ
MJ
BATTERY ON EQUALIZE
BYPASS
CAPACITY_EXCEEDEDm
MJ
MN/MJ
MN
Description of Condition Type alarm cutoff — can also indicate by adding " _ACO" to other conditions load transferred to engine battery on discharge battery disconnected battery being inadvertently equalize/boost-charged inverter, or UPS bypass mode near/exceeding capacity of plant, rectifier, etc. (m is optional rectifier #, etc.)
COML_AC_FAIL
COMMERCIAL AC FAIL MJ
AC_POWER
POWER_CONV(-MN/MJ) MN/MJ
CRANK_FAIL
GEN_OVR_CR
MJ commercial AC failure
DC-DC converter plant issue — 1 converter fail is minor, multiple is major engine has cranked too much and cannot start
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Table 13-2 Power Alarm Condition Types (page 2 of 5)
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CONDTYPE
CRITICAL
CTLLR_OK
DC POWER FAIL
DIFFERENTIAL_TEMP
DISCONNECT
ELAPSED
EMERGENCY_STOP
EMG_STOP_BUTTON
FAILm
PWR_ALM
FAIL_PARALLEL
GENERATOR FAIL TO PARALLEL
CR, MJ, or
MN
MJ
Description of Condition Type
CR
—
MJ
MJ/CR a critical power alm. (e.g., very low voltage, temperature differential) internal message (used with a watchdog) collocation DC power failure high/low differential temperature between batteries & ambient — criticality depends on threshold (see section of this document dealing with that issue)
MJ/MN/CR any disconnect operated (minor if there is redundancy)
MN
MJ an alarm has timed out (elapsed) standby engine emergency stop, or any other emergency stop
MJ
MN/MJ emergency stop button has been operated any equipment or plant failure — minor for individual rectifiers, ringers, or converters, major for multiples of these (m can be rectifier #, etc.) engine-alternators failed to parallel / synchronize
MJ rectifier, engine, or UPS fan fail alarm FAN
FUEL_LEAK
GEN_TANK
TANK
FUEL_SYS_TRBL
MJ
MJ any fuel tank leak
BLOWN DISCHARGE FUSE
TRIPPED BREAKER
FUSE/BRKR_OPERATE
FUSE
MJ
MJ/MN alarm from fuel system monitor. primary distribution fuse blown tripped DC distribution breaker any fuse or breaker operation
PRIMARY FUSE BREAKER TRIP
PWR_BOARD
GEN_BREAK
MJ
GEN_DAMPER
GEN_EXH_TE
GEN_FLCLOG
GEN_FREQ
GEN_HITEMP_PRE
GEN_LOTEMP
GEN_LO_VLT
GEN_OIL_LO
GEN_OIL_LO_PRE
GEN_OILTMP
GEN_TRBL-MJ
GEN_VLT_FQ
GENERATOR CRANK
BATTERY CHARGER FAIL
MJ
MJ
MJ
MJ
MJ
MN
MN
MJ
MJ
MN
MN
MJ
MJ
MJ engine-alternator output breaker tripped engine room/enclosure airflow damper failed engine exhaust temperature too high engine fuel line/filter clogged engine-alternator output frequency is abnormal pre-warning that engine may overheat and shut down engine is cold (may not start), possibly because coolant heater has failed low engine-alternator output voltage low engine oil pressure / level causing an engine shutdown pre-warning of low engine oil pressure or level high engine oil temperature generic engine major alarm abnormal engine-alternator output voltage or frequency engine start battery charger fail
GENERATOR DAY TANK LOW FUEL
MJ
GENERATOR HEATER FAIL MJ low fuel alarm from the day tank engine heater failure
GENERATOR HIGH COOLANT
TEMPERATURE SHUTDOWN
GEN_HITEMP
GENERATOR LOW BATTERY VOLTAGE
MJ
MJ
MJ engine shutdown due to high temperature engine start battery low voltage
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Table 13-2 Power Alarm Condition Types (page 3 of 5)
Chapter 13
Standard Alarm Messages and Thresholds for Power
CONDTYPE
CR, MJ, or
MN
Description of Condition Type
GENERATOR LOW COOLANT
LEVEL SHUTDOWN
GENERATOR LOW COOLANT
TEMPERATURE
MJ
MN engine shutdown due to low coolant level warning that engine coolant temperature is low, so it may have trouble starting
GENERATOR LOW OIL
PRESSURE SHUTDOWN
MJ
GENERATOR MAIN TANK LOW FUEL
GENERATOR TROUBLE
GROUND_FAULT
MN/MJ
GENERATOR NOT IN AUTO MN
GENERATOR PHASE MJ
GENERATOR TANK RUPTURE BASIN
MJ
MJ
MJ
GENERATOR SYSTEM GROUND FAULT
HI_BAT_VLTG
HI_VLT
HIGH VOLTAGE ALARM
HIGH FLOAT VOLTAGE
RECTIFIER HIGH FLOAT VOLTAGE
MJ engine shutdown due to low oil pressure low fuel in the main tank engine controls or transfer switch not in the “auto” position engine-alternator output phase problem fuel leak into a containment basin or the the interstitial space generic engine trouble alarm ground fault detected and AC possibly disconnected at engine or HSP engine alternator breaker opened due to a ground fault condition high DC plant voltage
HIGH
HIGH_FLOAT_AMPS
HIGH_FREQUENCY
MN/MJ
MN
MJ
HIGH_TEMPERATURE MN/MJ/CR any high temperature (environment or equipment)
HIGH_VOLTAGE MJ any high voltage, AC or DC
HIGH_VOLTAGE_HVSD any high fluid level or pressure float current is higher than it should be; indicating batteries near end-of-life
UPS or standby engine high frequency
CR the rectifier(s) have shut down on high voltage
HIGH VOLTAGE SHUTDOWN
IMBALANCE MN
INPUT_FAIL
INTER_FAIL(-MN/MJ)
MN/MJ
MN/MJ current is imbalanced between phases, battery strings, or rectifiers any AC or DC input fail ring plant interruptor fail – minor for 1, and major for both
INVERTER BYPASS NOT AVAILABLE
INV_BP_NOT_AVAIL
INVERTER ON BYPASS
INVTR_XFR
INVERTER FAIL
INVTR_FAIL(-MN/MJ)
INVERTER OUTPUT FAIL
INVTR_FAIL_OUTPUT
INVERTER GENERAL TROUBLE
INVERTER LINE LOSS
INVERTER TRIPPED BREAKER
LIGHTNING
LOCKOUT
LOW_FUEL
MJ
MN/MJ
MN
MN/MJ
MJ
MJ
MJ
MJ
MJ
MJ inverter bypass unavailable inverter on bypass (major if auto-switching not possible) inverter transferred to alternate source inverter failure (minor if N+1 redundant) or generic inverter major or minor generic inverter alarm inverter AC input fail tripped inverter breaker lightning detector has disconnected AC power and MGN input or output locked out (turned off or failed)
Low fuel level in tank
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Chapter 13
Standard Alarm Messages and Thresholds for Power
Table 13-2 Power Alarm Condition Types (page 4 of 5)
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CONDTYPE
CR, MJ, or MN
Description of Condition Type
LO_BAT_VLTG
LO_BAT_VLT
LOW VOLTAGE ALARM
LOW FLOAT VOLTAGE
LO_VLT
LO_VOLT_DISCONNECT
LOW VOLTAGE DISCONNECT
LOW
LOW_TEMPERATURE
LOW_VOLTAGE
MAJOR
DC MAJOR
MAJOR_CRITICAL
MICROPROC_FAIL
MINOR
DC MINOR
MULTIPLE_ALARMS
NORMAL
OFF_(NORMAL)
OFF_NORMAL
OIL LEAK
OPERATE
MJ
CR
MN/MJ
MN/MJ
MJ/CR
MJ
MJ
MJ
MN
OUTPUT
OVERCURRENT
OVERRIDE
OVERSPEED
GEN_OVR_SP
GENERATOR OVERSPEED
PROPER_OPERATION
RECHARGE
RECTIFIER
RECTIFIER LOSS OF PHASE
RECTIFIER MINOR
CHARGER FAIL
RECTIFIER MAJOR
RECTIFIER FAIL
RECTIFIER
RELAY_OPERATE
RESTART
RESET
RESTORE
MJ
MJ
MN
MJ
MN
MN
MJ
MN
MJ
MN/MJ
MN
MN
MN
MN battery on discharge or low float voltage plant, battery, or load disconnect due to low voltage any low fluid level or pressure any low temperature, including engine block heater fail low voltage (AC/DC, includes battery discharge) – may be critical for UPS any generic major alarm from the power plant any power major or critical — used when not enough points the microprocessor in the PSMC or power plant has failed any generic minor alarm from the power plant
MJ
MN
MN
MN/MJ
MJ
MN/MJ used when PSMC has to upgrade an alarm from minor to major any normal position (e.g., transfer switch) equipment normally off equipment not in a "normal" functioning condition engine oil leak detected a switch or other device has operated — criticality depends on the alarm. If this is simply a status alarm, it is a minor. It is a major for all other cases output failure excessive current on distribution, rectifiers, etc. the override of any function engine overspeed (shutdown) proper operation for any equipment indicates batteries are recharging
UPS battery charger failure loss of an AC input phase to a rectifier single rectifier failure multiple rectifier failures rectifier failure (minor if one, major if more than one) any relay has operated equipment has restarted any reset condition any restored condition
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Table 13-2 Power Alarm Condition Types (page 5 of 5)
Chapter 13
Standard Alarm Messages and Thresholds for Power
CONDTYPE
CR, MJ, or MN
REVERSE_POWER
GENERATOR REVERSE POWER FAIL
RING_FAIL(-MN/MJ)
RING GENERATOR TROUBLE
RING_XFER
SECONDARY FUSE/BREAKER TRIP
SEQUENCE
SHUNT_FAIL
STBY_ENG_FAIL
GENERATOR ENGINE FAILURE
GEN_FAIL
STBY_ENG_RUN
GENERATOR RUNNING
GEN_RUN
SURGE_ARRESTOR
SURGE_ARRE
LIGHTNING_PROTECT
TVSS FAILURE
TEMPERATURE
TEMP_PROBE
TIMER
TRANSFER
UNABLE_FLOAT
UPS ON BATTERY
BAT_BACKUP
UPS LOW BATTERY
UPS BYPASS NOT AVAILABLE
UPS ON BYPASS
UPS ON GENERATOR
UPS NO REDUNDANCY
UPS NORMAL
UPS_FAIL-MN
UPS_FAIL
UPS SHUTDOWN
UPS SUMMARY ALARM
UPS TROUBLE ALARM
VERY_LOW_VOLTAGE
LOW VOLTAGE DISCHARGE
RECTIFIER VERY LOW VOLTAGE
LO_LO_VOLT
VOLTAGE_OUT_OF_LIMIT
BAT_VOLT
WATCHDOG
MJ
MN/MJ
MJ
MN
MJ
MN
MN
MJ
MN
MJ
MN/MJ
MN
MN
MN
MJ
MJ/CR
CR
MJ
CR
MJ
CR
CR
MJ
MN
MN
MJ
RO
MN the PSMC is not working
Description of Condition Type alternator output power is reversed (now acting as a motor) ring plant minor or major – 1 ring generator failure is minor ring plant trouble transfer between ring generatorsy (usually due to a failure of one) fuse blown or breaker tripped at the BDFB (don’t connect to PSMC) rectifiers are sequencing back on line to avoid engine overload shunt board/communications failure standby engine/alternator has failed standby engine/alternator running
AC surge protector problem high or low temperature (used when unable to distinguish) temperature probe fail sequence, engine, etc., timer or other type of timer problem or timeout any transfer (ring, inverter, etc.) plant voltage controller unable to switch to float voltage
UPS batteries on discharge – criticality depends on backup time & loads very low UPS battery voltage
UPS bypass path is presently not available
UPS in bypass mode
UPS being fed by engine(s) loss of redundant UPS module(s)
UPS in a normal condition (doesn’t create a remote alarm) generic UPS minor alarm
UPS has failed / shut down generic UPS alarm very low voltage use when alarming device can't distinguish high and low
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Table 13-3 Reduced Character and Overhead Bitstream TL1 Alarm Condition Types
(page 1 of 2)
CONDTYPE
(ALMTYPE)
BATDSCHRG
BATT-DISCHARGE
LOVOLTAGE
LWBATVG
RECTLO
BATMIDVOLT
BATTDISC
BATTERY
BATTTEMP
CKTBRKR
COMLACFAIL
COMM-PWR-FAIL
POWER
CPMAJOR
N48B1MJ
CPMINOR
N48B1CR
DIFFTEMP
ENGINE
GEN
ENGOPRG
DISTFUSE
FUSE
FUSE-FAIL
HIFLOATAMP
HI-LOVOLT
HIVOLTAGE
RECTHI
LIGHTNING
LOWFUEL
LOW_FUEL
LWFUEL
LVDDISC
LVDFAIL
N48B1MJCR
N48B1MN
OVERCURNT
RECTCAP
PWR-48
RECT
RECTFAIL
RECT-FAIL
13-14
CR, MJ, or MN
NTFCNCODE
Description of Condition Type
(some of this may be used in the 40-character ALMMSG field)
"battery discharging"
MJ
"low battery voltage"
"rectifier low voltage"
MN/MJ battery string midpoint voltage imbalance (see Table 13-14)
MJ
MJ
MJ
MJ battery disconnect breaker manually or automatically operated
"battery failure" high battery temperature any breaker operated
MJ
MJ
MJ
MN
CR
CR
MJ
MN
MJ
MN
MJ
MJ
MJ
MJ
CR
CR
MJ
MN
"commercial power failure"
“centralized power plant major alarm”
“centralized power plant minor alarm” high differential temperature between batteries and ambient
“engine failure” or
“generator failure”
“engine operating”/running
"fuse failure" float current is higher than it should be; indicating battery end-of-life high or low DC plant voltage high DC plant voltage
"high rectifier voltage"
TVSS surge arrestor alarm, or lightning detector AC/MGN disconnect
“low fuel” alarm for the tank feeding the engine low voltage disconnect switch operated low voltage disconnect device has failed power major or critical – used when not enough points any power minor alarm combined on this point
MN plant “load exceeds” 80-100% of n-1 “rectifier capacity”
MN/MJ/CR "48 Volt power supply fail"
"rectifier failure"
MN/MJ
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Table 13-3 Reduced Character and Overhead Bitstream TL1 Alarm Condition Types
(page 2 of 2)
CONDTYPE
(ALMTYPE)
RECTRINGFL
RINGFUSE
RINGMN
RINGMJ
WATCHDOG
VHILOVOLT
CR, MJ, or MN
NTFCNCODE
MJ
MJ
MN
MJ
MJ
CR
Description of Condition Type
(some of this may be used in the 40-character ALMMSG field) ringer in a rectifier shelf failed ringing distribution fuse operated ringing plant generic minor (e.g., one ring generator failed, etc.) ringing plant generic major (e.g., both ringers failed, etc.) battery monitor or power monitor failure very high or very low voltage
Some CenturyLink ™ power alarms wire to switch scan points before routing to either
NMA ® , or to the NetCool™ SNMP agent (see section 13.6 for more information on
SNMP Power messages), depending on the legacy company to which the site belonged.
There are essentially 4 switch types in CenturyLink ™ that have power alarms routed through their scan points so that they eventually end up in NMA ® , where they are translated by a script into TL1 messages, as shown in the following tables:
For DMS ™ 10s, the SRCE field used to have only 4 characters. More recent software in these switches allows 16-characters in the SRCE field, with newer naming standards; however most power and environmental alarms were put in DMS ™ 10s in the days of 4character mnemonics. Scripts translate these SRCE codes to the dynamic unit and TL1
Condition Type of Tables 13-4 – 13-7, which appear on the NMA ® ticket. The description shown in the last column is scripted to appear on the event log of the dynamic ticket.
External scan points 1-21 and 60-64 in the DMS ™ 10 switches are pre-assigned (no matter what is wired to them, their name can’t be changed). Table 13-4 describes those preassigned points that are specific to centralized power plants (there are other power points among the pre-assigned list, but they are internal switch power-related alarms; and there are other pre-assigned points not shown here which are not specific to power at all). Note that any one of these points (or all of them) may not have anything wired to them; as the power points may have been hooked up to user-assignable scan points, or to e-telemetry devices, or to power monitors with TL1 capabilities.
Table 13-4 DMS
™
10 Pre-Assigned Scan Point Messages for Power Plants
Scan
Point
DMS ™ 10
SRCE
(and CLAS if relevant)
1 PWR (MAJ)
7 SWRG
9 PWR (MIN) new
16-char. (max) scripted standard
"dynamic unit"
BATPLT
RNG_TRANSFER
BATPLT new
20-character (max) scripted standard
"TL1 condition type"
BATPLT_ MJ
RNG_TRANSFER_MN
BATPLT_ MN
DESCRIPTION major power alarm residual ring plant transfer minor power alarm
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Scan points 22-59 (and possibly additionally 60-64 in sites without an e-tel system) can be user-assigned. Once wired, the DMS ™ 10 SRCE field can be changed in the switch
(via a direct log channel) in the NMA ® .monitor mode. Enter input mode by "sending":
#### (re-enter if the switch interrupts the session with its own output messages). Get into the scan point overlay by sending: ovly alrm<CR>. Print all scan points by querying with: que alpt all<CR>. Once the appropriate point is found, change it by
"sending" the command: redf alpt ##<CR>. The switch asks for inputs. Use appropriate messages from Tables 13-4 through 13-6 when prompted for the SRCE. If more than 1 point uses the same 4-character mnemonic, they are given sequential numbers (e.g., 1, 2, 3 …) in the IDNT field (e.g., if there are multiple rectifier fail minors from individual rectifiers).
For DMS ™ 100s, the UNIT TYPE field (not to be confused with NMA’s Unit/Shelf field) may contain up to 16 characters, and is the equivalent of the SRCE field of the
DMS ™ 10s. The present standards for these messages (as suggested by Nortel) are also found in the first column of Table 6, Parts 1-3. These will also be translated by the scripts.
An unfortunate thing about switch messages for power is that they don’t specify plant voltage and polarity, nor which plant it is (some offices have more than one plant). Due to this shortcoming, a generic descriptor of BATPLT is used in the TL1 message.
Northern Telecom (the original manufacturer of the DMS ™ switches) suggested different messages for essentially the same alarm. For example, in one site, a commercial AC fail might be called an ACPF, while in another site it is a PWR2. CenturyLink ™ has defined both as a COML_AC_FAIL. Several of the alarms are this way.
The script applies to all DMS ™ switches. Although the 4-character messages are used mostly in DMS ™ 10 switches, the installing technician may have liked the 4-character mnemonic message and used it in a DMS ™ 100 even though he/she had 16 available character spaces.
The messages in the first column of the tables must be met exactly for the script to recognize them. The script only looks for whole messages, as shown in the table, not partial phrases. The messages in the switch must be entered in all capitals for the scripts to recognize them.
The NMA ® switch scripts assign the “dynamic type” of “power” for power messages.
DMS ™ user-assignable scan-point messages follow in Table 13-5:
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Table 13-5 DMS
™
User-Assignable Scan Point Power Standards for NMA
®
Chapter 13
(page 1 of 3)
DMS ™ message
ACIM
BATF
BATPLT_FAIL
ACPF
ACFAIL
COMACFAL
LPF
PFA
PFM
PWR2
PR001-PR005
CPF
CRPWR
MJPWR
MNPWR
CFA
CONVFUSE
CFL
CONVFAIL
CMAJ
CONVMAJ
CMIN
CONVMIN
ACG
ENGF
ENGFAIL
ENGR
ERUN
DIESL_RUN
PR006-PR010
EAMJ
STBYENGMJ
EAMN
STBYENGMN
EBFL
ENGBATCHG
ECRK
CRANKFAIL
PR011-PR015
ECHT
ENGHITEMP
ECLT
ENGLOTEMP
OSPD new
16-char. (max) scripted standard
"dynamic unit"
COML_AC_IMBAL
BATPLT_BAT_FAIL new
20-character (max) scripted standard
"TL1 condition type"
COML_AC_IMBAL_MN
BATPLT_BAT_FAIL_CR
COML_AC_FAIL
BATPLT
BATPLT_CRITICAL
BATPLT_MAJOR
BATPLT_MINOR
CONV_DIST_FUSE
CONV_FAIL
CONVPLT_MAJOR
CONVPLT_MINOR
STBY_ENG_FAIL
STBY_ENG_RUN
STBY_ENG_MAJOR
STBY_ENG_MINOR
ENG_BATCHG_FAIL
ENG_CRANK_FAIL
COOLANT_HITEMP
COOLANT_LOTEMP
COML_AC_FAIL_MJ
BATPLT_CR
BATPLT_MJ
BATPLT_MN
BATPLT_CRITICAL_CR
BATPLT_MAJOR_MJ
BATPLT_MINOR_MN
CONV_DIST_FUSE_MJ
CONV_FAIL_MJ
CONVPLT_MAJOR_MJ
CONVPLT_MINOR_MN
STBY_ENG_FAIL_MJ
STBY_ENG_RUN_MN
STBY_ENG_MAJOR_MJ
STBY_ENG_MINOR_MN
ENG_BATCHG_FAIL_MJ
ENG_CRANK_FAIL_MJ
COOLANT_HITEMP_MJ
COOLANT_LOTEMP_MN
DESCRIPTION imbalance between phases of commercial AC entire battery supply failed, power lost commercial AC failed
Commercial Power any power plant alarm in a DMS ™ 10. Its criticality depends on the "classification" (CLAS) field, where the input will be "CAT", "MAJ", or "MIN", respectively, or
"NONE" (no alarm will come across if "NONE" is entered) critical power alarm major power alarm minor power alarm converter distribution fuse alarm individual converter failure generic converter plant major alarm generic converter plant minor alarm standby generator failed standby engine running
Generator Run generic engine major alarm generic engine minor alarm engine start battery charger failed engine failed to start
Generator Start Failure engine overheating engine coolant low temperature
ENG_OVERSPEED ENG_OVERSPEED_MJ engine running too fast and AC frequency
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Table 13-5 DMS ™ User-Assignable Scan Point Power Standards for NMA ® (page 2 of 3)
NDC
PR072-PR092
PR042-PR062
PR093-PR113
HF
HV
HIGHVOLT
IFL
INVFAIL
PR114-PR134
IXFR
INVXFER
BATD
BATT
LOWBATT1
LOWBATT2
LV
BATDISCHRG
DISCHG
DISCH
FLOAT
LVOLT
48HL
LIGHTNING
LTNG
LIGTN
LVD
MPFL
RATELMJ
RATELMN
DMS ™ message new
16-char. (max) scripted standard
"dynamic unit" new
20-character (max) scripted standard
"TL1 condition type"
DESCRIPTION
FTBL
FUEL
ENG_FUEL_TRBL
ENGALT_FUEL_LOW
ENG_FUEL_TRBL_MJ
ENGALT_FUEL_LOW_MJ generic fuel system problem (e.g., leak, low fuel) low fuel alarm
LEAK
FUEL_LEAK
XFER
ENG_FUEL_LEAK ENG_FUEL_LEAK_MJ fuel leak
XFR
TRNSW_TRANSFER TRNSW_TRANSFER_MN AC transfer switch operated
PR016-PR020 TRNSW_OFF_NORMAL TRNSW_OFF_NORMAL_MJ Transfer Switch Failure
DFA
PWRRMFUSE power plant distribution fuse or breaker operated
BATPLT_FUSE_BRKR
BATPLT_FUSE_BRKR_MJ
BATPLT_HIGH_VOLT
INV_FAIL
INV_TRANSFER
BATPLT_LOW_VOLT
BATPLT_HILO_VOLT
LIGHTNING
LOW_VOLT_DISC
BATPLT_MP_FAIL
BATPLT_MAJOR
BATPLT_MINOR
BATPLT_PSMC
BATPLT_FUSE_BRKR_MN
BATPLT_HIGH_VOLT_MN
BATPLT_HIGH_VOLT_MJ
INV_FAIL_MJ
INV_TRANSFER_MN
BATPLT_LOW_VOLT_MJ
BATPLT_HILO_VOLT_MJ
LIGHTNING_MJ
LOW_VOLT_DISC_CR
BATPLT_MP_FAIL_MJ
BATPLT_MAJOR_MJ
BATPLT_MINOR_MN
BATPLT_PSMC_MJ
DC input to a piece of equipment lost or failed
Power Distribution Major Alarm
Power Distribution Critical Alarm
Power Distribution Minor Alarm minor power plant high voltage alarm major high power plant voltage inverter plant fail alarm
DC/AC Converter Fail Major Alarm inverter transfer between AC/DC low power plant voltage or battery on discharge high or low battery plant voltage lightning protector failed/operated low voltage disconnect operated/failed power plant controller microprocessor failure generic power major coming from PSMC generic power minor coming from PSMC power monitor alarm PM
LAC
POWR
RECFAIL
RECTIFIER
RECT
BATPLT_RECT_FAIL BATPLT_RECT_FAIL_MN single rectifier fail
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Table 13-5 DMS
™
User-Assignable Scan Point Power Standards for NMA
®
Chapter 13
(page 3 of 3)
DMS ™ message new
16-char. (max) scripted standard
"dynamic unit" new
20-character (max) scripted standard
"TL1 condition type"
DESCRIPTION
NAC
PWR1
PR021-PR041
FUSE
RINGFUSE
RINGFAIL
RINGGEN
RINGMAJ
RMAJ
RMIN
RINGMIN
RXFR
RINGXFR
UPS
RNG_FUSE
RNG_FAIL
RNG_RGEN_FAIL
RNG_MAJOR
RNG_MINOR
BATPLT_RECT_FAIL_MJ
RNG_FUSE_MJ
RNG_FAIL_MJ
RNG_RGEN_FAIL_MN
RNG_MAJOR_MJ
RNG_MINOR_MN two or more rectifiers failed commercial AC or multiple rectifier failure
Charger/Rectifier Fail Major Alarm residual ringing plant distribution fuse alarm both ring generators failed single generator on residual ring plant failed ring plant major (e.g., all ring generators or fuse fail) ring plant minor (e.g., single ring generator failed)
RNG_TRANSFER
UPS_FAIL
RNG_TRANSFER_MN
UPS_FAIL_MJ residual ring plant transferred from primary to secondary
UPS failure
UPST UPS_TRANSFER UPS_TRANSFER_MN UPS transferred between AC/DC
VLV
WDOG
BATPLT_V_LO_VOLT BATPLT_V_LO_VOLT_CR very low battery voltage — plant loss imminent
PSMC_WATCHDOG PSMC_WATCHDOG_CR PSMC failed
WATCH
DMS ™ 100 remote locations (usually remote switches, but sometimes RTs) aren’t correctly identified when the alarm messages of Table 13-5 are scripted across. In these cases, it appears as if the alarm comes from the host. To rectify this problem it is necessary that the first column message be preceded by the 4-character designation by which the host recognizes the remote (this can usually be found in the "site" table of the host in NMA ® ). This should be followed by underscore, and then the message of column 1. The scripts will then recognize the remote, and give the appropriate CLLI ™ code on the alarm ticket.
As an example, Wilcox is a remote DMS ™ 100 out of a Tucson host. A fire alarm in the
Wilcox CO switch would be WLX1_FIRE, while it would be only FIRE in the host office.
The NMA host-remote relationship table ("ocs_hrsm_id") in NMA ® may also need to be updated. This relationship table lists the 4-character (or more) remote designation, and assigns the proper CLLI ™ code to it (a valid CLLI ™ that is listed in the scc_clli screen of
NMA ® ) The script calls this table when it recognizes a remote designation.
There are also RTs and/or remote switches whose alarms come to the scan points of
DMS ™ 10 switches. In this case, the 4-character designation of the remote terminal is automatically transmitted to NMA ® and does not need to be made a part of the message as with the DMS ™ 100. However, the relationship between the 4-character remote identifier and its corresponding CLLI ™ code do need to be in the ocs_hrsm_id screen.
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In the rare cases where DMS ™ 10 remote scan point messages must be changed by accessing the remote through the host instead of a direct channel, each message must be preceded by the "satellite number" of the remote.
RTs (e.g., SLC ® , Seiscor, DISC*S ® , Litespan, e.g.) that are integrated into DMS ™ 100s are identified differently. The alarm text is placed in the MISCTEXT field in switch table
RCSINV, and severity is defined in the ALMSEVER field. The text appears in the PM128 switch messages. The PM128 message has a “pair gain” identifier which consists of the
SITE name, frame number and unit number of the RCS (e.g. PG50 95 0). The NMA ® script looks for this ID and goes to the host-remote relationship tables. These “pair gain”
IDs (which are larger than 4-characters) need to be built in the ocs_hrsm_id screen.
All of the “remote” alarms listed so far use the messages from Table 13-5. Integrated
DMS ™ -1 Urban power and environmental alarms in DMS ™ 100 switches may use these, or they may use a predefined set of standards in the RCUALRMS table, as shown in
Table 13-6. The first 6 points of this table should be populated automatically with these predefined standards by entering the command: NIL_TEXT. The last 6 alarms are user-assignable and should use messages from the first column of Table 13-5 (the first 6 should be filled with user-assignable messages only when the point wired to them doesn’t match the description shown in the last column of Table 13-6). The Urban
Remote Terminal site location is identified in the message by the 4-character identifier described above, and the host-remote relationship table must be populated.
The dynamic unit of power alarms coming from Remote Terminals is preceded by
"RT_".
Table 13-6 Power Messages for Integrated DMS ™ -1 Urban
Code present
Nortel standards new
16-char. (max) scripted standard
"dynamic unit" new
20-char. (max) scripted standard
"TL1 condition type"
DESCRIPTION
1 20 this is a cabinet intrusion alarm (environmental), so it Is not "power"
1 21 LOW BATTERY VOLTAGE RT_BATPLT_LOW_VOLT RT_LOWVOLT_MJ battery on discharge
1 22
1 23 this is a cabinet temperature alarm (environmental), so it is not "power" this alarm is a sync alarm not to be sent to power worklists
RT_COML_AC_FAIL RT_ACFAIL_MJ commercial AC fail or rectifier fail this is a fuse and breaker alarm that doesn’t belong to power worklists 1 25
RECTIFIER FAILED
1 26
1 27
1 28
1 29
1 30
1 31 these are user-assignable scan points if used for power or environmental alarms, they should use the messages of Tables 13-4 or 13-5
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DMS ™ switches also support the integration of other types of digital loop carrier (DLC) systems directly into the switch (without going through a universal COT bay). The most common power alarm that comes from these other types of DLC systems
(especially Lucent/AT&T/Western Electric SLC ® systems) is a generic power/miscellaneous alarm (which typically means that the site is on batteries — caused by an AC fail or rectifier/charger fail). This has been scripted in NMA ® to flow through as a seprate power alarm if it is the first alarm to come in from that integrated
DLC. If it is not the first alarm from the site to create a ticket, then it will generally show up as another condition type on a toll facilities ticket. The location field on these alarm tickets is the switch CLLI ™ code. The dynamic or miscellaneous type is typically s96 (for SLC ® 96; although not all DLC Systems are SLC), and the dynamic unit or miscellaneous designation is the DLC system ID (e.g., sid 45). The condition type reads: r.t. power/acfail
There are some newer types of DMS ™ remote switch modules such as OPAC ™ , RLCM ™ ,
OPM ™ , and RSC ™ which are capable of being installed in different environments, including cabinets. Those remote DMS ™ switch modules in cabinets report their alarms through the host as OPMPES Output Messages (such as PES100, PES107, PES115, etc.), along with various text messages describing the alarm and a remote identifier (the remote is identified on the ticket using the same process described earlier in this section). The NMA ® script picks out the appropriate text for power alarms and creates the messages found in Table 13-7. (The script does not search for the rectifier numbers; therefore, the 0/1 below in the messages can be ignored.)
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Table 13-7 NMA
®
Power Messages for Nortel Remote Switches in RTs
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OPMPES Messages
Clr
State new
16-char. (max) scripted standard
"dynamic unit" new
20-character (max) scripted standard
"TL1 condition type"
PES100 alarms cleared by PES107 messages
DESCRIPTION & Notes
Rectifier 0/1
Common AC
FSP State
BCC Fuse 0/1
Cur Limit 0/1
High Temp.
Low Temp.
LOAD BUS
LOW VOLTAGE
ALARM
CHARGE BUS
LOW VOLTAGE
ALARM
Fail OK
OPAC_CAB_PWR
RECT_FAIL_MN
COML_AC_FAIL_MJ
FUSE_BRKR_OPERATE_MJ any single rectifier fail — this becomes a
RECT_FAIL_MJ if both are in
AC power failure distribution fuse failed rectifier fuse failed
RECT_OVERCURRENT_MJ high rectifier current high or low cabinet temperature — can
LOW_TEMPERATURE_MJ cause switch failure if in too long
PES104 alarm cleared by PES107 “Common AC OK” or “Rectifer 0/1 OK” message
Fail OK
Fail OK
OPAC_CAB_PWR VERY_LOW_VOLTAGE_MJ
Battery voltage below -47.0 VDC — as noted above, this alarm is cleared by return of commercial AC and rectifiers
PES105 alarm cleared by PES106 message
OPAC_CAB_PWR LOW_FLOAT_MJ
Battery charging bus voltage is too low to float the batteries — cleared by “CHARGE
BUS OK” on PES 106
PES113 alarms cleared by PES107 messages
BCC Fuse 0/1 Fail OK OPAC CAB PWR FUSE BRKR OPERATE MJ internal pwr plant controller fuse fail
PES115 and PES117 alarms cleared by PES107 “BCC Unit OK” message
? (PES115)
? (PES117)
Fail OK OPAC_CAB_PWR BAT_STRING_FAIL_MJ any PES115 or PES117 message indicates that the batteries won’t take a charge (are bad) and need to be replaced — cleared with a “BCC Unit OK” on PES107
For Alcatel-Lucent 5ESS ™ s, there are standards for some power alarms. The standards differ between hosts and remotes. Lucent’s preassigned standards for these messages are on the left side of Tables 13-8 and 13-9. Scripts in NMA ® translate these messages to the 16-character TL1 messages shown in the 2 nd column of the Tables. The description in the last column the Tables appears on the dynamic ticket’s event log. The messages of these 2 Tables are preassigned by Lucent and can’t be changed on those scan points
(these messages may also be applied to “user-assignable” scan points if they are short enough). If someone wishes to bring in a rectifier fail in a remote 5ESS ™ , it is preferable that they physically connect the alarm to scan point 37, where the message is prebuilt.
In many cases with 5ESS ™ s, there are alarms which do not have a standard message, or where an alternate standard message is acceptable, or where the standard message in
Tables 13-8 and 13-9 is too lengthy. A "user-assignable" scan point can be programmed with a message. In these cases, the message in the 5ESS ™ needs to be changed to the standards of column 1 in Table 13-10 (or Tables 13-8 and 13-9 if their message is short enough). When this is done, the scripts can do the translations as explained.
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The primary power and environmental alarms for the host switches can be found on the
105 and 106 pages (another set of miscellaneous scan points viewed on the 119 page may also have power or environmental alarms) of the NMA ® SCC module, and they are on the 1400 page for the remotes. Changes can be made to the messages in the hosts from a command line or the 120 page. The change message for the host would look as follows: chg:alm,bpsc=XX,tag=“MESSAGE”
Where XX designates the scan point number, and MESSAGE is the message from the column 1 of Table 13-10 in all CAPITALS. Changes in remotes can be made by going to the 196 page, and choosing options 8, then 11. This should bring up the “remote alarm assignment” screen, which has 9 fields. After identifying the remote and scan point in fields 1 and 2, the message can be changed in field 7 (TTY field) with a message from the first column of Table 13-10. User-assignable scan points for 5ESS ™ hosts are 6902-
6927 and 7700-7747. For remotes, it is scan points 2-31. There are 9 characters available for user-assignable scan points in hosts, and 20 characters available in remotes.
The remote scan point assignment mentioned allows the user to specify whether they are hooking up a normally open or normally closed alarm. There is no such specification for host scan points. In a host, normally open (close on alarm) contacts are connected between the NO and C (common) on the OAU (Office Alarm Unit) M00 block on the frame. (This block is wired back to the switch’s OAU in switch mod M00.) Normally closed (open on alarm) alarms are connected between the NC and C contacts; and the
NO and C contacts must be jumpered. For those messages in the first column of Table
13-10 that are followed by a “CR”, “MAJ”, or “MIN” in parentheses; this signifies that the “Alarm Level” field should be toggled appropriately. This is simply for clarification on these specific alarms since the message is the same otherwise. All alarm levels should be set at the level indicated in the third column. present
5ESS ™ standards
HM6933MJRECT FAIL
HM6940MJALM BAT
HM6941MJCO BAT DSCHG
HM6942MJSTBYPLT FUEL
HM6942MJSTBYPLT OPER
HM6942MJSTBYPLT RECT
HM6942MJSTBYPLT FAIL
HM6946MJHIGH VOLTAGE
HM6947MJCOM PWR FAIL
Table 13-8 5ESS
™
Standard Power Messages for Hosts new
16-char. (max) scripted standard
"dynamic unit" new
20-character (max) scripted standard
"TL1 condition type"
DESCRIPTION
BATPLT RECT FAIL BATPLT RECT FAIL MJ rectifier(s) fail
BATPLT_MAJOR BATPLT_MAJOR_MJ major power alarm
BATPLT_LOW_VOLT BATPLT_LOW_VOLT_MJ low plant voltage
ENGALT_FUEL_LOW ENGALT_FUEL_LOW_MJ engine fuel tank low
STBY_ENG_RUN STBY_ENG_RUN_MN engine running
ENGALT_BATCHG
STBY_ENG_FAIL
ENGALT_BATCHG_MJ engine start battery charger
STBY_ENG_FAIL_MJ standby engine failed
BATPLT_HIGH_VOLT BATPLT_HIGH_VOLT_MJ high power plant voltage
COML_AC_FAIL COML_AC_FAIL_MJ commercial AC failed
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Table 13-9 5ESS
™
Standard Power Messages for Remotes
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Scan
Point present
5ESS ™ standards
(TTYNAME) new
16-char. (max) scripted standard
"dynamic unit" new
20-character (max) scripted standard
"TL1 condition type"
DESCRIPTION
32 DISCHARGE FUSE FAIL
37 RECTIFIER FAILURE
BATPLT_FUSE_BRKR BATPLT_FUSE_BRKR_MJ power plant dist. fuse or brkr.
BATPLT_RECT_FAIL BATPLT_RECT_FAIL_MN rectifier fail
38 ALM BATTERY FAILURE BATPLT_MAJOR BATPLT_MAJOR_MJ major power alarm
39 CO BATTERY DISCHARGE BATPLT_LOW_VOLT BATPLT_LOW_VOLT_MJ battery on discharge
40 HIGH VOLTAGE
41 COMM POWER FAILURE
42 STBY PLANT LOW FUEL
BATPLT_HIGH_VOLT BATPLT_HIGH_VOLT_MJ high power plant voltage
COML_AC_FAIL
ENGALT_FUEL_LOW ENGALT_FUEL_LOW_MJ engine fuel tank low
43 STBY PLANT OPERATING STBY_ENG_RUN
44 STBY PLANT RECT FAIL
45 STBY PLANT FAILURE
ENGALT_BATCHG
STBY_ENG_FAIL
COML_AC_FAIL_MJ commercial AC failed
STBY_ENG_RUN_MN engine running
ENGALT_BATCHG_MJ engine start batt. charger fail
STBY_ENG_FAIL_MJ standby engine failed
Table 13-10 5ESS
™
User-Assignable Scan Point Power Message Standards (page 1 of 2) recommended standard 5ESS ™
"user-assignable" scan point message new
16-char. (max) scripted standard
"dynamic unit" new
20-character (max) scripted standard
"TL1 condition type"
DESCRIPTION
ALM BAT (CR)
DIST FUSE
BATPLT_CRITICAL BATPLT_CRITICAL_CR generic critical power alarm
BATPLT_FUSE_BRKR BATPLT_FUSE_BRKR_MJ power plant distribution fuse or brkr.
-24V FA
-48V FA
AC IMB
AC FAIL
CONV PLT (MAJ)
CONV PLT (MIN)
CONV FUSE
CONV FAIL
CONVFAIL
CLT HIT
CLT LOT
ENGBATCHG
ENGBATVLT
ENG CRK
ENGLOWTR
ENGWTRTMP
FUEL LOW
FUEL LEAK
FUEL TRBL
ENG OSPD
ENGLOOIL
DSL RUN
ENG FAIL
24VPLT_FUSE_BRKR 24VPLT_FUSE_BRKR_MJ 24 volt plant distribution fuse or brkr.
48VPLT_FUSE_BRKR 48VPLT_FUSE_BRKR_MJ 48 volt plant distribution fuse or brkr.
COML_AC_IMBAL COML_AC_IMBAL_MN imbalance between phases of AC
COML_AC_FAIL xxCONVPLT_ALARM
COML_AC_FAIL_MJ commercial AC failed
CONV PLT (mj) generic converter plant major or minor
CONV_DIST_FUSE
CONV_FAIL
COOLANT_HITEMP
CONV PLT (mn)
CONV_DIST_FUSE_MJ
CONV_FAIL_MJ alarm on switch scan point xx converter distribution fuse alarm individual converter failure
COOLANT_LOTEMP COOLANT_LOTEMP_MN engine coolant low temperature
ENG_BAT_CHG
ENGBAT_HILOVOLT ENGBAT_HILOVOLT_MJ high or low voltage on engine start
ENG_CRANK_FAIL
ENG_LOW_WATER
ENG_WATER_TEMP ENG_WATER_TEMP_MJ
ENGALT_FUEL_LOW ENGALT_FUEL_LOW_MJ engine fuel tank low
ENG_FUEL_LEAK
ENG_FUEL_TRBL
ENG_OVERSPEED
ENG_LO_OIL_PRES
STBY_ENG_RUN
STBY_ENG_FAIL
COOLANT_HITEMP_MJ
ENG_BAT_CHG_MJ
ENG_CRANK_FAIL_MJ
ENG_LOW_WATER_MJ
ENG_FUEL_LEAK_MJ
ENG_FUEL_TRBL_MJ
ENG_OVERSPEED_MJ
ENG_LO_OIL_PRES_MJ
STBY_ENG_RUN_MN
STBY_ENG_FAIL_MJ engine overheating engine start battery charger problem engine failed to start low coolant level in the engine high or low engine coolant temperature fuel leak generic fuel system problem engine running too fast low engine oil pressure engine running standby engine failed while running
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Table 13-10 5ESS
™
User-Assignable Scan Point Power Message Standards (page 2 of 2) recommended standard 5ESS ™
"user-assignable" scan point message
ENG ALT (MAJ)
ENG ALT (MIN)
AC XFR
AC XFR FL
INV FAIL
INV XFR
RECTFAIL
HILOVOLT
-24V HVLV
-48V HVLV
VOLT LOW
VOLT VLOW
VOLT HIGH new 16- character
(max) scripted standard
"dynamic unit" new 20-character
(max) scripted standard
"TL1 condition type"
ENG ALT (mj) xxSTBY_ENG_ALARM
ENG ALT (mn)
TRNSW_TRANSFER TRNSW_TRANSFER_MN
TRANSFER_FAIL TRANSFER_FAIL_MJ
INV_FAIL INV_FAIL_MJ
INV_TRANSFER INV_TRANSFER_MN
BATPLT_RECT_FAIL BATPLT_RECT_FAIL_MN
BATPLT_HILOVOLT BATPLT_HILOVOLT_MJ
24VPLT_HILOVOLT 24VPLT_HILOVOLT_MJ
48VPLT_HILOVOLT 48VPLT_HILOVOLT_MJ
BATPLT_LOW_VOLT BATPLT_LOW_VOLT_MJ
BATPLT_VLO_VOLT BATPLT_VLO_VOLT_CR
DESCRIPTION generic engine major or minor alarm on switch scan point xx transfer switch operated transfer switch failed to operate inverter plant fail alarm inverter transfer rectifier fail high or low power plant voltage high or low 24 V power plant high or low 48 V power plant low voltage or battery on very low battery voltage
VOLT HI
LIGHTNING
PSMC WDOG
PSMCWDOG
PSMCm (MAJ)
PSMCm (MIN)
OMNI MJ
POWER (MAJ)
POWER (MIN)
BATPLT_HIGH_VOLT BATPLT_HIGH_VOLT_MJ
LIGHTNING LIGHTNING_MJ
PSMC_WATCHDOG PSMC_WATCHDOG_CR
PSMC_MAJOR
PSMC_MINOR
BATPLT_MAJOR xxBATPLT_ALARM
PSMC_MAJOR_MJ
PSMC_MINOR_MJ
BATPLT_MAJOR_MJ
POWER (mj)
POWER (mn) high power plant voltage lightning protector failed
PSMC failed backup power major from PSMC backup powerminor from PSMC power major from PSMC generic power major or minor alarm on switch scan point xx
RNG FUSE
RNG PLT (MAJ)
RNG PLT (MIN)
RNG GEN
RNG XFR
UPS FAIL
UPS XFR
RNG_FUSE
RNG_MAJOR
RNG_MINOR
RNG_RGEN_FAIL
RNG_TRANSFER
UPS_FAIL
UPS_TRANSFER
RNG_FUSE_MJ
RNG_MAJOR_MJ
RNG_MINOR_MN
RNG_RGEN_FAIL_MN
RNG_TRANSFER_MN
UPS_FAIL_MJ
UPS_TRANSFER_MN ring plant distribution fuse alarm ring plant major ring plant minor ring generator failed ring generators transferred
UPS failure
UPS transferred
For any message in Table 13-10, if there is more than one of a particular piece of equipment, such as multiple rectifiers, converters, DC plants, ring plants, etc.; a number designating the individual piece of equipment needs to be placed after the column 1 message to prevent multiple alarms from coming in against the same NMA ® ticket. For example, in a site with 4 RFA alarms (one for each rectifier), the alarms would be:
RECTFAIL1, RECTFAIL2, etc. In a similar fashion, where space allows, other characters may be placed before or after the first column message to indicate location in the building, or other relevant information. In either case, these alarms would route to the appropriate worklists because they contain the keywords from Table 13-10. By scanning the original message in the switch, all of the relevant information intended to be conveyed can be found.
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All 5ESS ™ switch scan point messages report to NMA through the host switch. If the alarm comes from a remote switch, there is another field (besides the TTY message field) populated with RBPSC. This is a clue to the NMA ® script to look in the remote identifier field. The remote identifier field of the raw alarm message coming to NMA uses the abbreviation SM for switch module, followed by a number (e.g., SM 19). This number uniquely identifies the remote switch. The NMA ® script then goes to the ocs_hrsm_id tables to match the remote number with the CLLI ™ code for that remote switch site.
In rare cases, RT site alarms will be transported over distance and wired to switch scan points. If it's a remote switch, the remote ID (switch module) field cannot be used, as this is already populated with the remote ID (SM). So, the same thing is done as with the
DMS ® 100 switches (i.e., the first part of the message is populated with a 4-character remote identifier followed by a space and then the message per Table 7 [if you are spacelimited, use the 4-character messages from Table 13-5]). The NMA ® script looks at the first four characters and attempts to match them to a remote from the ocs_hrsm_id tables. If a remote designator is matched, then that CLLI ™ code is populated for the ticket. If no remote designator is found, the scripts will assume that the alarm is attached to the host or remote site as the case may be.
5ESS ™ switches also support the integration of other types of DLC systems directly into the switch (without going through a universal COT bay). The most common power alarm that comes from these other types of DLC systems (especially from SLC ® systems) is a generic power/miscellaneous alarm (which typically means that the site is on batteries — usually caused by an AC fail). The location field on these alarm tickets is the switch CLLI ™ code. The dynamic or miscellaneous type is typically the type of DLC system (e.g., s96 for SLC ® 96), and the dynamic unit or miscellaneous designation is the
DLC system ID (e.g., sid 45). The power condition type reads: r.t. power/acfail
Ericsson scan points (referred to by Ericsson as “external” alarms) are easy to connect and name. Ericsson doesn’t have a recommended naming standard. The CenturyLink ™ standards for power plant and environmental messages are shown in the first column of
Table 8. Ericsson provides two fields for describing the scan point (external) alarm in
ASCII text, known as CAW1 and CAW2 (or Slogan1 and Slogan2). The standard message in the first column of Table 8 is placed in CAW1.
An NMA ® script will translate and direct the power messages of the first column of
Table 13-11 to the power worklists. This script will create a “dynamic” ticket in NMA ® , and create the messages in the second and third columns of Table 13-11. The script will look for the full complete message (not partial message) of the first column in CAW1.
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Ericsson Standard
(CAW1 Field) new 16-char.
(max) scripted standard
"dynamic unit" new 20-char. (max) scripted standard "TL1 condition type"
DESCRIPTION
AC FAIL
AC FAIL TO RECTIFIER
AC POWER FAIL
AC POWER FAILURE
AC REC POWER FAIL
COMMERCIAL POWER FAILURE
COMM POWER FAIL
COMMERCIAL POWER FAIL
MAINS FAILURE
-48 V POWER PLANT
+130V CONVERTOR FAIL
+130V MINOR
+130V CONV. FAIL
+130V CONVERTER FAIL
-130 V CONVERTOR FAIL
-130V CONV. FAIL
-130V MINOR
-130CONVFAIL
-130PLT FAIL
+130V PLTFAIL
+130V PLANT FAIL
-130V PLANT FAIL
+130V CONV MAJOR
-130V MAJOR
+130V MAJOR
-130V FUSE
-130V FUSE ALARM
+130V FUSE
+130V FUSE ALARM
-48V FUSE ALARM
-48V FUSE
48V FUSE ALM
FUSE MAJOR
-48V POWER FUSE
FUSE 48VOLT PLANT
FUSE 48 VOLT PLANT
POWER PLANT FUSE
-48V MPF
LINEAGE 2000 FUSE
MN DISTFUSE
DISCH FUSE
GENERATOR BATTERY FAIL
COML_AC_FAIL COML_AC_FAIL_MJ commercial AC failed
BATPLT_FAIL
CONV_FAIL
CONVPLT_FAIL
BATPLT_FAIL_MJ
CONV_FAIL_MN
CONVPLT_FAIL_MJ
CONVPLT_MAJOR CONVPLT_MAJOR_MJ
ENG_BAT_FAIL ENG_BAT_FAIL_MJ power plant controller failure single converter failed converter plant failed converter plant generic major
— distribution fuse or multiple converter fail engine start battery failure
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Ericsson Standard
(CAW1 Field) new 16-char. (max) scripted standard
"dynamic unit" new 20-char. (max) scripted standard "TL1 condition type"
DESCRIPTION
ENGINE RUNNING
ENGINE RUN NORMAL
SBY ENG PROPER OPERATE
COMMPOWER/DIESEL RUNNING
GENERATOR RUN
GENERATOR RUNNING
GEN SET RUNNING
ENG RUN
DIESEL PROPER OPERATE
DIESEL OPERATE (ENGINE)
DIESEL OPERATE
ENGINE FAIL
SBY ENGINE ENGINE FAIL
GENERATOR FAIL
GENERATOR FAILED
GEN SET FAILURE
DIESEL FAIL(ENGINE)
DIESEL FAIL
SBY ENG RECT FAIL
ENGINE RECTIFIER FAIL
ENGINE BATT CHG FAIL
FUEL TANK RUPTURE
LOW GENERATOR FUEL
GEN SET LOW FUEL
HIGH VOLTAGE
HI VOLTAGE
-48V PLT HIGH VOLT
-48V L2000 HIGH VOLT
-48V HIGH VOLTAGE
POWER PLANT HI VOLTAGE
48V H/L VOLTS
-48V HIGH/LOW VOLTAGE
HI/LO VOLTAGE
LOW VOLTAGE
LO VOLTAGE
-48V LOW VOLTAGE
-48V L2000 LOW VOLT
-48V PLT LOW VOLT
48V PLANT FLOAT VOLT
48V FLOAT VOLTAGE
-48V BATT DISCHG
BATTERY DISCHARGE
BATTERY ON DISCHARGE
BATTERIES ON DISCHARGE
BATT DISCHARGE
CO BATT DISCHARGE
BATTTERY DISCHARGE
STBY_ENG_RUN
STBY_ENG_FAIL
ENG_FUEL_LEAK
STBY_ENG_RUN_MN
STBY_ENG_FAIL_MJ
ENG_FUEL_LEAK_MJ engine running engine failed while running fuel tank has a leak
BATPLT_HIGH_VOLT BATPLT_HIGH_VOLT_MJ high power plant voltage
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Ericsson Standard
(CAW1 Field) new 16-char. (max) scripted standard
"dynamic unit" new 20-char. (max) scripted standard
"TL1 condition type"
DESCRIPTION
-48V VERY LOW VOLT
VERY LOW VOLTAGE
RATELCO MAJOR
RATELCO POWER MAJOR
RATELCO MAJ
RATELCO MJ
OMNPLSE MAJOR
OMNI MAJOR
-48V PLANT MAJOR
-48V PLT MAJOR
-48V POWER MJ
POWER MAJOR
MAJOR POWER
LINEAGE 2000 POWER
LINEAGE 2000 MAJ
RATELCO MINOR
BATPLT_V_LO_VOLT
BATPLT_MAJOR
RATELCO POWER MINOR
RATELCO MIN
RATELCO MN
OMNPLSE MINOR
OMNI MINOR
POWER MINOR
POWER MN.
LINEAGE 2000 MIN
BATPLT_MINOR
LINEAGE 2000 PROCESSOR BATPLT_MPROC
48V RECTIFIER FAIL
BATPLT_V_LO_VOLT_CR very low power plant voltage
BATPLT_MAJOR_MJ
BATPLT_MINOR_MN
BATPLT_MPROC_MJ power plant generic major power plant generic minor power plant controller fail
-48V RECT FAIL
-48V RECT G1 FAIL
-48V RECT G2 FAIL
-48V RECT G3 FAIL BATPLT_RECT_FAIL BATPLT_RECT_FAIL_MN single rectifier fail
-48V RECT G4 FAIL
-48V RECTIFIER FAIL
48V RFA
RECTIFIER FAIL
-48V RECT MAJ
-48V RECTIFIER MAJOR
RING PLANT MAJ.
LORAIN RINGING
RING PLANT
RINGING PLT MAJOR
AUX RING PLANT-MJ
PECO RINGING MACHINE
RING PLANT TBL
BATPLT_RECTS_FL
RNG_MAJOR
BATPLT_RECTS_FL_MJ
RNG_MAJOR_MJ multiple rectifier failures ring plant major — both ringers failed, or ringing distribution fuse
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Ericsson Standard
(CAW1 Field)
AUX RING PLANT-MN
RING PLT MN
RINGING PLT MINOR
RING PLANT MN.
TRANSFER SWITCH OPERATE
TRANS SW PROPER OPERATE
TRANSFER SW OPER
ENGINE SW OFF NORM
SBY ENG SWCH OFF NORMAL
RATELCO WD
RATELCO WATCH DOG
RATELCO WATCHDOG
OMNI WATCHDOG
OMNPLSE SYS TRBL
WATCH DOG
WATCHDOG new 16-char. (max) scripted standard
"dynamic unit"
RNG_MINOR
TRNSW_TRANSFER new 20-char. (max) scripted standard
TL1 condition type"
RNG_MINOR_MN
TRNSW_TRANSFER_MN
PSMC_WATCHDOG PSMC_WATCHDOG_CR
DESCRIPTION ring plant minor — single ringer failed auto transfer switch operated properly power monitor has failed
The Ericsson AXE ™ switch CAW2 field is used for alarm type descriptions and remote site identification (all scan point alarms come through the host). The scripts that direct and translate for power worklists look in CAW2 to determine if the alarm comes from a remote switch. If the CAW2 field matches an identifier in NMA ® ’s host-remote tables, the identifier will be translated to the proper CLLI™ for display on the dynamic ticket. If no remote designator is found, the script assumes the alarm is attached to the host site.
13.3 TL1 Query Messages for Power
A power monitor or a mux equipped for X.25 or IP communication may get messages, as well as send the SIDs, AIDs, and condition types defined earlier. The messages that these machines may get (along with a couple of “report out” messages) from NMA ® in
TL1 language are defined below. Each machine, depending on the manufacturer, will not accept all of the messages listed below, only the ones that have been programmed into that machine's hardware and software (the minimum required power monitor messages have been marked with an asterisk). The message shown below is not the complete message; most messages include the AID and other commands defining what the user is looking for. See the Telcordia ® (Bellcore) GRs-811, 833, and associated documents (or the manuals for the monitor) for the correct and complete formats.
When the alarm device is communicating to NMA ® via SNMP traps which are translated via a template to TL1 messages, the TL1 queries from NMA ® (see the table below) are translated by that same template/script into SNMP “Get” messages.
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Table 13-12 TL1 Query Messages for Power
MESSAGE
ACT-USER
ALW-MSG-ALL
ALW-MSG-EQPT
CANC-USER
DLT-SECU-USER
ED-DAT
ED-SECU-USER
ENT-SECU-USER
INH-MSG-EQPT
INIT-REG-EQPT
INIT-SYS
MEAS-CUR
MEAS-VG
OPR-ACO-ALL
OPR-ACO-EQPT
OPR-EXT-CONT
RLS-EXT-CONT
EXPLANATION
* a logon (not required if software configured correctly) not necessary if the software doesn't restrict messages allow an individual alarm message to be sent
* a logoff if ACT-USER was used remove a TL1 user edit date and/or time modify a TL1 user's privileges, passwords, etc. add a TL1 user prevent an alarm message from being sent initialize register: turn statistics on/off, erase highs and lows reboots the system measure current measure voltage masks or removes all alarms operate alarm cutoff for individual alarm operates a control relay (e.g., shutdown rectifier) releases the operated control relay (e.g., turn rectifier back on)
RTRV-ALM-ALL * retrieves all alarms
RTRV-ALM-ENV retrieve alarm information from "environmental" alarms info for a specific overhead bitstream housekeeping alarm
RTRV-ALM-EQPT * retrieve a specific alarm or all active alarms, depending on the PSMC
RTRV-ATTR
RTRV-ATTR-ENV
RTRV-EXT-CONT
RTRV-HDR
RTRV-MMREPT retrieve alarm security (major, minor, etc.)
Retrieve information for overhead bitstream alarm points
RTRV-ATTR-EQPT retrieve alarm security (major, minor, etc.) for a specific alarm
RTRV-EQPT
RTRV-PM-ALL
RTRV-PM-EQPT
RTRV-SECU-USER
RTRV-TH-EQPT
SET-ACO-EQPT
SET-ATTR-ENV
SET-ATTR-EQPT
SET-SID
SET-TH-EQPT retrieves the settings for a specific AID (channel) retrieve the state of an external control relay or contact
* retrieves header info on site and monitor reports analog readings for a particular AID
REPT^ALM^ENV retrieves readings, histories, and statistics for all channels retrieve current readings, statistics, or highs and lows retrieve a list of authorized TL1 users retrieve alarm thresholds for a specific alarm set up the alarm cutoff mode
Change the classification and messages of an overhead alarm change the classification (major, minor, etc.) of an alarm set the office name or name of the alarm device set the thresholds for a specific alarm
REPORT MESSAGES (these precede the actual alarm message to NMA cause an environmental alarm and verify output
REPT^ALM^EQPT * cause a power alarm and verify output
® )
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Analog points are derived from reading actual voltage or current levels within the system and delivering alarms based on the analog levels or combinations of various analog levels and binary states.
Analog points are based on temperature, voltage, current, or a combination of analog and binary information. The following tables describe the values that should be associated with the various analog levels.
In many cases, both minor and major alarm thresholds are listed for each type of alarm.
For voltage and temperature set-points, typically only the major alarm is required (if both major and minor values are listed) and the minor alarm is optional if the monitor type allows it, and/or there are enough spare points. For capacity exceeded alarms on current, it is preferable to have both major and minor thresholds (where they exist, but as a bare minimum, the minor should be provisioned.
The tables contain values that can be programmed into a monitor, or can be measured manually with portable instruments and compared.
It is useful before setting thresholds to know the approximate float voltages or normal settings of various DC and AC plants, and the following table summarizes these:
The nominal AC voltage levels found in Table 13-13 come From Article 220.5A of the
National Electric Code (NEC ® ), and should be used in AC computations.
Note that some older 130 V battery plants may have CEMF cells. These should be removed when the plant is replaced or at the next convenient opportunity.
This document (and others) reflects a transition from a traditional flooded leadantimony average float voltage of -2.17 to -2.20 Volts per lead-calcium flooded cell (as recommended by flooded battery manufacturers) in order to provide more reliable batteries. The further stipulation is that all new -48 V battery plants have 24 batteries per string, providing a float voltage of approximately -52.80 V for flooded lead-calcium strings. Sites that won’t function with a float voltage of -2.20 V/cell (some older plants cannot easily have the float voltage raised to -52.80 V due to HVSD settings, etc.) must be configured at the traditional -2.17 V/cell. For lead-calcium batteries that cannot be raised due to alarm or HVSD settings, perhaps the float can be raised part of the way
(for example, -52.50). This is better for these batteries than the traditional -52.08.
Whole string boost or equalize charging should only be used in rare cases to quickly recover battery capacity (such as a PV application, or batteries that have been stored too long offline).
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Table 13-13 Typical Output Voltage Settings nominal
Voltage
Description Typical
-48 VDC float voltage for 37-cell string of Ni-Cd batteries float @ 77°F with 1.215 s.g. flooded batteries or VRLAs with 1.240-1.250 s.g.
-24 VDC float @ 77°F with 1.215 s.g. flooded batteries or VRLAs with 1.240-1.250 s.g. float @ 77°F with 1.240 s.g. flooded lead-selenium batteries
-48 VDC
-52.9 – -52.6
-52.80
-26.40
-53.52 float voltage @ 77°F for -48V plants with 1.280-1.295 s.g. VRLAs finish charge for solar systems with VRLAs (no more than 4 hrs)
-53.8 – -54.2
-55.7 float voltage for plants with nominal 52 V float Li-ion packs; or 23-cell VRLAs -52.08 – 52.3 float voltage for -48VDC plants with nominal 53.8 – 56 V float Li-ion packs
32 VDC
24 VDC
12 VDC
-48 VDC float voltage for 38-cell string of Ni-Cd batteries
32 VDC
24 VDC
12 VDC float voltage @ 77°F with 1.260-1.295 s.g. batteries float voltage @ 77°F with 1.300 s.g. VRLAs
(this is the most common gravity for VRLAs)
-48 VDC float voltage @ 77°F for -48VDC plants with 1-310-1.335 s.g. VRLAs
-53.8 – -55.2
35.87 – 36.13
26.9 – 27.1
13.45 – 13.55
-54.4 – -55.1
54.0 – 54.5 initial charge volt (100-250 hrs) for flooded lead-acid (multiply by # series cells) 2.37 – 2.50
-2 VDC flooded round cell or lead-calcium single-cell boost/equalize charge (250 hours)
-2 VDC Flooded lead-selenium single-cell boost/equalize charge (for 72 hours)
24/48/130 string equalize voltage for most plants
12/24/48/60 Finish charge for photovoltaic/solar plants
-24/-48 rectifier fallback voltage if controller fails
36.0 – 36.33
27.0 – 27.25
13.5 – .13.68
-54.8 – -55.2
-2.50
-2.40
=float ±0.1
=float + ~4%
=float ±0.1 extended range -48 to 130 VDC converter plant output voltage setting
-48/145 -48 to 145 V converter plant output setting
-48/190 -48 to 190 V converter plant output setting
120 VAC single-phase low-line AC output (e.g., some inverters and small UPS)
240/120 split-single-phase AC
208 Y three-phase wye AC for small and medium-sized buildings
240 ∆ three-phase high/wild-leg delta AC voltages
480 Y three-phase wye AC for most larger buildings
528 – 540
24
48
130 VDC
135 – 137.5
145 VDC
190 VDC
120
240/120 V
208/120 V
240/208/120
480/277 V
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The points of the next table can be set at the PSMC, the conventional DC Plant
Controller, and/or the Rectifiers, depending on the manufacturer and model. When the same set point can be set in multiple places, the PSMC takes first priority (uses the levels given in the table), the Plant Controller second priority, and the Rectifiers final priority. In these cases, each successive priority level should be set approximately 0.5 V above or below (depending on whether it is a high or low voltage threshold, respectively) the previous value. For example, if I set the PSMC Low Voltage at –50 V, I can set the DC Plant Controller Low Voltage at –49.4 V, and the Rectifier Low Voltage at
–49 V.
The exception to this rule is for HVSD. In the case of HVSD, the controller should have the lowest voltage setting (-56.4 V, as shown in the table), and the rectifiers should be set at –56.9 V. If you want to ensure that only offending rectifiers stay off, you may need to turn off load sharing in switch mode plants, and ensure that the plant rectifier restart circuit works. If the switch mode rectifier plant is not capable of working without load sharing on, then it is best to set the rectifiers to the lower HVSD setting (if there are settings for both the rectifiers and controller). Generally, PSMCs (unless an integral part of the Plant Controller) are not wired for control features (per Chapter 8), so HVSD would not be set on them (or if it is set, it would be the last level of defense — e.g., at
-57.4 V).
It is generally not necessary to dual wire the same alarms (although backup major and minor alarms through a separate reporting device are encouraged). For example, if each rectifier fail is directly wired to the PSMC, the rectifier minor from the plant controller is probably not necessary.
Note that it is not necessary to have alarms for each of the values in the following tables.
Consult Chapter 8 for further guidance.
LVDs are generally discouraged (because they sometimes fail when they shouldn’t) unless required by the manufacturer of the served equipment, or to save Customer
Prem batteries. They are required (and are sometimes built into the charge controller) for stand-alone solar sites. They should generally be in series with only the batteries
(LVBD); and not directly in series with the load (unless required by an equipment manufacturer).
For all of these threshold tables where the threshold drives an output alarm, there may be a time delay before the alarm comes in to prevent nuisance alarms and to avoid premature action on “chattering” alarm relays. Almost always, time thresholds and number of reoccurrence thresholds in a certain time frame are managed by the receiving alarm management system (such as NMA ® or the SNMP manager). However, for particularly troublesome “bouncing” alarms, it is permissible to set a delay of a few seconds (up to 30) at the power monitor or plant controller if it is capable of such time thresholding.
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Table 13-14 Battery Plant Voltage Alarm Set Points nominal Description Priority Value
-48 VDC high float voltage (controlled environments only) Minor
Notes
+0.5 above float
24 VDC
12 VDC battery plant high voltage
-48 VDC -48 V battery plant HVSD
-24 VDC -24 V battery plant HVSD
12 VDC 12 V battery plant HVSD
-48 VDC
24 VDC
12 VDC battery plant low voltage / on discharge
Major
Critical
-55.4 -55.9 for VRLA batteries
27.6 27.9 for VRLA batteries
13.9
-56.4
-28.2
14.1
-51.0 no low float alarm; this value also used to start load-shed timer
-24 VDC -24 V battery plant very low voltage
-2 VDC
Major 25.5
12.9
Critical -46.0
-46.5 rarely available
-23.0
Minor -2.15
1.215 s.g. flooded lead-acid pilot cell low voltage
Major -2.13
1.215 s.g. flooded lead-acid pilot cell high voltage Minor
-2.25
-2.27
1.240 s.g. flooded lead-acid pilot cell low voltage
Minor -2.18
Major -2.16
-2.28
-48 VDC
-24 VDC
12 VDC
-48 VDC
-24 VDC
1.240 s.g. flooded lead-acid pilot cell high voltage Minor
-2.30
1.300 s.g. VRLA pilot cell low voltage
1.300 s.g. VRLA pilot cell high voltage low voltage battery disconnect (LVBD) battery plant LVD reconnect solar plant LVD disconnect/reconnect battery plant LVLD battery plant LVBD battery plant LVD reconnect battery plant LVLD battery plant LVBD battery plant reconnect
Minor
-2.22
-2.29
-40.0
-49.0
46-47 not usually used
Major -2.33 battery plant low voltage load disconnect (LVLD) Critical -42.0 rarely used
1.215 s.g. flooded lead-acid string high midpoint
1.215 s.g. flooded lead-acid string low midpoint
1.280-1.300 VRLA string high midpoint
1.280-1.300 VRLA string low midpoint
1.215 s.g. flooded lead-acid string high midpoint
1.215 s.g. flooded lead-acid string low midpoint
Critical
-24.5
10.5 rarely used
10.0
12.25
Minor -27.2
Major -28.0
Minor -25.6
Major -24.8
Minor -28.0
Major -28.6
Minor -26.4
Major -25.6
Minor -13.6
Major -14.0
Minor -12.8
Major -12.4
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Plant output of a converter plant without batteries should be set as near as possible to the nominal plant voltage. When it supports batteries, it should be set at the float voltages defined earlier in Table 13-13 with the corresponding thresholds found in
Table 13-14.
Table 13-15 Converter Plant (no batteries on output) Voltage Alarm Set Points nominal output
Voltage
Description Priority Value
12 VDC
-24 VDC
48 VDC
130 VDC
145 VDC
190 VDC high voltage low voltage high voltage low voltage
HVSD high voltage low voltage
HVSD high voltage low voltage
HVSD high voltage low voltage
HVSD high voltage low voltage
HVSD
Minor
12.5
11.5
24.5
23.5
Critical 29.0
Minor
49.0
47.0
Critical 56.0
Minor
140
125
Critical 141
Minor
149
140
Critical 151
Minor
199
180
Critical 201
To help mitigate the possibility of thermal runaway in VRLA batteries, the charge current flowing to the batteries can be limited by automatically lowering the float
Voltage as the battery temperature rises (this is temperature compensation). The recommended settings for temperature compensation devices are shown below (not all devices have each of these settings, so try to match those that apply to the particular device). An attempt should be made to get as close as possible to these settings, but not all devices will be able to match these settings. Voltage should not be lowered below open circuit (unless the extreme thermal runaway temperature is reached) in order to avoid severe loss of battery life.
Multiple temperature probes for multiple strings should be used (one per string), and compensation should be based on the highest temperature.
Not all compensation is slope compensation. An attempt should still be made to match the parameters shown in Table 13-16 (except for the slope parameter) when step compensation is all that is available.
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Many existing rectifiers used with VRLA batteries have voltage-sensing circuits inaccessible by temperature compensation devices. For these, to limit battery charge current, a Current Limiting device placed in series with each battery string may be used. In addition, some devices perform both compensation and current limiting functions, offering even greater protection from thermal runaway. The acceptable limits for current limiting devices (including battery recharge current limiting settings available in some rectifier shelf controllers) are shown in Table 13-16.
Table 13-16 VRLA Temperature Compensation and Recharge Current Limit Settings nominal
Voltage
Description Settings Notes
480 VDC
360 VDC
-48VDC
32 VDC
24 VDC
12 VDC
480 VDC
360 VDC
-48 VDC
32 VDC
24 VDC
12 VDC normal temp comp termination lower voltage highest voltage where compensation should stop
520
390
-52.0
34.6
26.0
12.9
559
419
-55.4
36.8
27.7
13.85
-51.3 V for low s.g.
VRLA
-25.6 V for low s.g.
VRLA recommended in controlled environments
≈ -1°C
480 VDC
360 VDC
-48 VDC
32 VDC
24 VDC potential deadband where temp comp is not active lowest temp comp temperature maximum temperature for slope temp comp
(to voltage given in first 6 rows of this table) final step temp comp temperature final step temp comp voltage
68-86°F (20-30°C)
30°F
135°F
167°F
480
360
48.0
32.0
24.0
≈ 57°C
= 75°C
-46.2 V for low s.g.
VRLA
-23.1 V for low s.g.
VRLA
= 79°C
12 VDC maximum battery disconnect temperature slope of compensation
12.0
174°F
-1.3 to -3.6 mV/cell/°C per battery manufacturer recharge current limit C/5-C/30 A C = 8-hr Ah rating
For the recharge current limit, as noted, C is the Amp-hour rating of the string at the 8hour rate to 1.75 V/cell at 77°F. For example, the current limit of a 100 A-hr battery string limited to C/20 would be 5 Amps.
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Care must be taken to ensure that current limiting doesn’t cause the plant to perform a
High Voltage ShutDown while attempting to recharge the batteries. This can happen on certain rectifiers if current limiting is set too tightly. For example, a type of rectifier may perform an HVSD while attempting to recharge if the current limiting is set for
C/20. In this case, the limits should be set for C/10. Check the documentation of the suppliers of the current limiting device and power plant to see if this may be a problem.
Also, because discharge current as well as recharge current passes through the current limiting device, ensure that the discharge current capacity of the device and its cabling is sufficient to meet the portion of the projected site load that will be placed on the individual string or group of strings served by the current limiting device.
There is no need to remotely report an alarm when temperature compensation or current limiting is active. However, battery temperature alarms or battery current alarms may be set in accordance with the guidelines given in Table 13-17.
Table 13-17 Power Temperature Alarm Set Points
Description power room low temperature in indoor non-RT sites power room high temperature in indoor non-RT sites controlled environment RT power room low temp controlled environment RT power room high temp controlled environment engine room low temperature controlled environment engine room high temperature flooded pilot cell low temperature flooded pilot cell high temperature controlled environment VRLA low temperature controlled environment VRLA high temperature battery temperature recognizing heater pad fail diesel engine coolant high temperature diesel engine coolant low temperature flooded battery – room differential temperature
VRLA – ambient differential temperature
Priority Value Notes
Minor
55°F Major alarm unnecessary
86°F = 30°C
52°F
95°F
47°F
93°F ignore during engine run
59°F
90°F Major alarm unnecessary
50°F
Minor 95°F = 35°C
Major 104°F = 40°C
Minor 27°F in RT or engine room
Minor 203°F
Major 215°F
Minor 87°F
Major 37°F
Minor 8°F
Major 12°F
Minor 12°F
Major 20°F
Engine room low temperatures do not have to be alarmed if the engine is equipped with block/coolant heater(s) and battery heating pad(s).
Because VRLAs are susceptible to thermal runaway, whenever the ability to monitor battery and/or differential temperature exists, it should be done; and is much more useful than room temperature alone; especially a differential temperature alarm.
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Current monitoring points shown below might or might not be monitored. "Major" power sources and primary DC distribution will be monitored. Table 13-18 covers all
DC current monitoring, as well as AC current monitoring for breakers and fuse capacity
(see Table 13-22 for AC load current capacity thresholds).
Table 13-18 Current Thresholds
Description battery discharge current string discharge current imbalance for the same chemistry and Ah rating flooded battery recharge current
VRLA battery recharge current
Li-ion battery current pure lead or lead-calcium battery float current pure lead or lead-calcium flooded battery float current lead-calcium or pure lead-tin VRLA float current pure lead or lead-calcium battery float current pure lead or lead-calcium flooded battery float current lead-calcium or pure lead-tin VRLA float current lead-selenium float current low-antimony VRLA float current foamed-plate Ni-Cd float current
UPS battery string AC ripple current
UPS VRLA monobloc string charge current AC ripple
UPS VRLA 2 V jar string AC ripple current flooded UPS battery string AC ripple current rectifier overcurrent
DC plant capacity
A/B (dual) feed fuse/breaker capacity true A/B (dual) feed current imbalance non-redundant feed fuse/breaker capacity
AC phase current imbalance for panel loaded > 20%
AC phase current imbalance for panel loaded ≤ 20%
Priority
Minor
Major
Minor
Major
Minor
Minor
Minor
Major
Minor
Major
Minor
Major
Minor
Minor
Major
Minor
Minor
Major
Minor
Major
Minor
Major
Minor
Major
Minor
Value Notes
80%
100%
30%
50%
C/150
C/50
80%
160% based on 4 or 8-hr rate from the average alarm in > 24 hrs before alarm center dispatches based on mfg max
60% above baseline
0.15 mA/Ah avg low current over min
1.5 mA/Ah controlled env & comp
250% 2½ times baseline
0.25 mA/Ah avg low current over min
2.5 mA/Ah controlled env & comp
250% 2½ times baseline
0.5 mA/Ah avg low current over min
400% 4 times baseline
0.8 mA/Ah avg low current over min
300%
5 mA/Ah
8 mA/Ah
500%
1000%
5 mA/Ah
150%
250%
1.2A/100W/cell Approximately equal to
2.4A/100W/cell
1.8A/100W/cell
101%
106%
80%
100%
40%
50%
10%
80%
15%
30%
3 times baseline for controlled enviro & temp comp
5 times baseline
10 times baseline assumes similar UPS load from baseline reading
IEEE-recommended
5 A / 100 Ah doesn’t apply to constantpower rectifiers smallest of bus, shunt, n-1 rectifier or recharge from the average of the 2
AC or DC from the avg for rectifier or mechanical panels
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When a minor current capacity alarm is exceeded, in order to avoid a standing alarm, the threshold can be raised in 5% increments or smaller until the situation is corrected. The major alarm threshold may not be raised.
Note that float currents at high temperatures will increase significantly without temperature compensation.
AC phase current imbalances should be on at least a few second time delay to allow for startup, and are not applicable to high-leg delta systems.
A big contributor to the shorter lives of most UPS batteries is lower frequency AC ripple on the DC bus (some coming from poor charger filtering, but most being poorly-filtered feedback onto the DC bus from the inverter). Ripple voltage is easily measured and is a major contributor to the amplitude of the ripple current, but the relatively low frequency
(below 667 Hz) ripple current damages the battery most. Battery manufacturers and the
IEEE have recommendations on maximum ripple current allowed (see Table 13-18); however, these are relatively high, and it would be much less damaging to the battery if the levels were even lower. Setting a baseline ripple current reading for a particular UPS with a particular battery model and a relatively constant load can be useful if the change from that is tracked and used to indicate when to replace filter capacitors in the UPS.
There are both permanent and portable test sets that can periodically use a discharge or an AC signal to determine the internal resistance (resistance meters use a short DC discharge) or impedance (impedance or conductance meters use an impressed AC signal) of a battery cell or monobloc (they are also often used to determine the microohm resistance of intercell connections) to determine whether it is good or close to the end of its life. While there is no direct linear correlation between an internal ohmic reading and the actual capacity of the battery, ohmic readings can be used to spot problem cells/monblocs and replace them before they cause a problem.
Table 13-19 Battery Ohmic Thresholds
Description Priority Value Notes
UPS or long duration VRLA battery resistance/impedance
UPS or long duration VRLA battery conductance/admittance Minor engine start battery conductance/admittance/CCA engine start battery resistance/impedance intercell connection resistance/impedance
Intercell connection conductance/admittance
Minor 130% baseline = 100%; and
Major 150%
77%
67%
Minor 50%
Major 32%
Minor 200%
Major 300%
Minor 120%
Major 150%
Minor 83%
Major 67% while manufacturerprovided baselines can be used, the best baseline is read approximately 90 days after installation (for new installations, the average of all the readings can be used as a baseline)
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AC voltage measurements are defined as the rms (effective) voltage difference between any two conductors of the circuit. The actual level of the voltage is determined by the phase of the circuit (single or 3 phase), configuration, and the base voltage.
Table 13-20 AC Voltage Thresholds nominal
AC Voltage
120 line-neutral
208 line-line or line-neutral
240 line-line
277 line-neutral
480 line-line
Description low voltage (& return to commercial) engine start low level
AC fail level high voltage (& return to commercial) engine start high level low voltage (& return to commercial) engine start low level
AC fail level high voltage (& return to commercial) engine start high level low voltage (& return to commercial) engine start low level
AC fail level high voltage (& return to commercial) engine start high level low voltage (& return to commercial) engine start low level
AC fail level high voltage (& return to commercial) engine start high level low voltage (& return to commercial) engine start low level
AC fail level high voltage (& return to commercial) engine start high level
Priority Value
Major 103 V
101 V
132 V
Major 187 V
133 V
182 V
231 V
Major 207 V
203 V
264 V
Major 249 V
266 V
245 V
294 V
Major 432 V
425 V
504 V
509 V
Fuel Tanks come in many sizes. Engine manufacturers will give gal/hr consumption at full-rated load, from which tank size is computed; or similarly, reserve hours remaining in the tank can be computed by dividing the consumption rate into the gallons.
Table 13-21 Fuel Alarm Thresholds
Description Priority Value Notes low fuel alarm for the main tank
Minor 50% of tank size
Major 25% (not below 12 hrs)
Low fuel alarm for the day tank Major high diesel fuel alarm
Propane tank overfill
Major
Major
5% below the “call to fill” sensor
90-95%
80-85%
If only 1 alarm, must be
Major may only be a local alarm
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For example, a low fuel major alarm on a fully-filled tank with 96 run hrs at full engine load would be set at 25% of tank volume (24 full load run hours left); however, for an existing fully-filled tank with only 36 run hrs of capacity at full load, the low fuel major would be set at 12 full-load run hrs (33% of tank volume) rather than at 9 hrs (25% of tank volume) in order to have a little more time to find a refueler in disaster situations.
Table 13-22 kW/kVA or AC Ampere Load Capacity Thresholds
Description redundant UPS, PDU or transformer kW/kVA or AC
Ampere load redundant inverter or engine kW/kVA or AC Amp load non-redundant kW/kVA or AC Ampere load
Priority Value
Minor 40%
Major 50%
Minor 80%
Notes of n-1 capacity
Major 100%
Minor 80%
For AC load capacity, it is preferable to monitor and threshold kW or kVA due to varying power factor; however, this is not always possible, so AC Amps may be used.
13.5 Typical Power Alarm and Monitor Points
Due to cost, it is not feasible to alarm everything in a site. This section serves as a guide to which alarm, monitor, and control points to connect for different types of sites.
The more information that can be communicated via alarming, the better analysis and dispatch will be. A CEV, hut, Radio site, or small CO (CdO) may have one small battery plant, no engine, a ring plant, and may or may not have converters or inverters.
Therefore, there will not be many alarms. Sample points for small sites are listed below in Tables 13-23 through 13-25.
ALARM commercial AC Power Failure generic Power (plant) Major generic Power (plant) Minor single Rectifier Failure (RFA)
Multiple Rectifier Failures
DC Plant Fuse/Breaker Operated
Battery on Discharge / Low Voltage (LVA)
High DC Plant Voltage and/or HVSD
Battery Disconnect and/or LVD
Surge Arrestor Fail
Ring Plant Major
Ring Plant Minor
Converter Plant Minor
Converter Plant Major
Table 13-23 Typical Power Alarm Points for Smaller Sites Without Engines
Criticality Description/Notes
Major
Major
Minor
Minor
Major
Major
Major
Major input power to the rectifiers has failed power plant major or generic power major from monitor power plant minor or generic power minor from monitor a single rectifier has failed more than one rectifier has failed any fuse or breaker alarm at the DC plant plant voltage is low and/or the battery is on discharge the batteries are being overcharged
Major/Critical individual strings, or all batteries disconnected
Major
Major
Minor
Minor
Major the TVSS/SPD has failed ring plant major (if there is a ring plant) ring plant minor (single ringer/interrupter fail/transfer) individual converter failure (if there is a converter plant) converter plant fuse alarm, multiple converters failed, etc
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In some Prems, RTs, etc., the only transport is via fiber mux housekeeping or overhead bits. While some muxes have 16 or more hka bits for the alarms of Table 13-23, others have a limited set of overhead bits for power alarms, as per Tables 13-24 and 13-25.
Table 13-24 Typical Power Alarm Points for Small Sites With Only 4 Overhead Bits
ALARM(s)
Commercial AC Power Failure
Low DC Plant Voltage / Battery on Discharge single Rectifier Failure multiple Rectifier Failures, Fuse Fail, or other
Criticality Description/Notes
Major
Major power has failed to the rectifiers batteries are on discharge
Minor one rectifier has failed
Major multiple rectifiers failed, fuse/breaker tripped, etc.
Table 13-25 Typical Power Alarm Points for Small Sites With Only 2 Overhead Bits
ALARM(s) generic Power Major generic Power Minor
Criticality Description/Notes
Major AC Fail, BOD, power fuse alarm, high voltage, etc.
Minor single rectifier fail, or any other power minor
Table 13-26 lists “typical” power alarm points for larger sites, such as those with a permanent engine-alternator. Configurations for these types of sites and their alarming vary, so it would be impractical to list every possible alarm found in these locations.
Therefore, this Table serves as only a guide to the most common points.
Table 13-26 Power Points for Larger Sites with Engines (page 1 of 2)
ALARM individual Rectifier Failure (RFA)
Multiple Rectifier Failures generic Power (plant) Major generic Power (plant) Minor
DC Plant Fuse/Breaker Operated
Battery on Discharge (BOD) / Low Voltage
Very Low Voltage
High DC Plant Voltage (HVA)
High Voltage ShutDown (HVSD)
Battery Disconnect
Battery Major/Failure
Battery Minor
Power Monitor/Controller Watchdog
Criticality
BATTERY/RECTIFIER PLANT
Minor
Major
Major
Minor
Major
Major
Critical
Major
Critical
Major
Major
Minor
Major a single rectifier has failed more than one rectifier has failed generic power plant or power monitor major alarm gneeric power plant or power monitor minor alarm any fuse (FA) or breaker alarm at the main PBD(s) batteries are on discharge or are not charged up nearing the end of battery discharge (optional) the batteries are being overcharged rectifiers have shut down due to very high voltage battery disconnect device (breaker?) open (when used) power monitor/controller microprocessor failure
RING PLANT
Description/Notes available from some smart batteries or monitors
Ring Plant Major and/or Ring Plant Fuse Alarm Major multiple ringers/interrupters or fuse failed
Ring Plant Minor or Ring Generator Failure Minor single ringer/interrupter failed, or ringer transfer
UPS
UPS Fail/Major
UPS on Bypass
UPS Battery on Discharge / Low Voltage
Major
Minor
UPS fail or other major UPS alarm
UPS in an abnormal state (e.g., on bypass, etc.)
Major/Critical UPS is on battery (criticality depends on loads & time)
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Table 13-26 Power Points for Larger Sites with Engines (page 2 of 2)
Inverter on Bypass
ALARM
Inverter Fail/Major alarm
Inverter Bypass Not Available
Commercial AC Power Failure
Surge Arrestor Fail
Ground Fault Detection
Criticality
INVERTER PLANT
Description/Notes
Major
Minor
Major inverter plant fail or other inverter major alarm inverter on alternate source (when equipped) inverter bypass isn’t available (when equipped)
COMMERCIAL AC
Major
Major
Major
AC power to the site has failed the TVSS/SPD has failed
AC source locked out due to a large ground fault
STANDBY ENGINE standby Engine Run
Load Transferred to Engine
Single-Phase Lockout
Engine Controls or Transfer Switch Not in Auto
Engine Start Battery Charger Fail or Low Voltage
Engine Fail
Engine OverCrank
Engine Emergency Stop Button engine shutdown due to Low Coolant
Minor
Minor
Major
Minor
Major
Major
Major
Major
Major the backup engine is running transfer switch operated properly (optional) some transfer switches won’t work if a phase fails engine controls not returned to Automatic after test engine start battery charger failed or battery low volts the backup engine has failed engine shutdown due to High Coolant Temperature Major (optional) if these alarms are combined into
Engine OverSpeed Major generic engine fail engine shutdown due to Low Oil Pressure Major
Engines Failed to Parallel
Fuel System Trouble alarm
Fuel Leak
Major
Major
One or more engines failed to sync to the bus generic fuel system problem (e.g., leak, low fuel)
Low Fuel (Main Tank)
Low Fuel (Day Tank – where equipped)
Major
Minor/Major
(optional) if combined into generic fuel system trouble
Major
CONVERTER PLANT
Converter Plant Minor
Converter Plant Major individual Converter Failure
Minor
Major
Minor use only if other alarms that make up this major and minor are not remoted to NMA
® generic or individual converter fail(s)
Converter Plant Distribution Fuse Alarm Major generic converter distribution fuse alarm(s)
For further information on monitoring and optional versus required points, see Chapter
8 of this Tech Pub.
13.6 Power SNMP Traps
Many DSL and Ethernet based systems in the Legacy Qwest Local Network portion of
CenturyLink ™ report their alarms via SNMP Traps to MicroMuse’s NetCool™. This is also true for CO-based alarms in Legacy CenturyTel (they often route their alarms through translation devices that create the SNMP traps). Table 13-27 lists some of the common SNMP traps for power-related alarms found in various CenturyLink ™ companies.
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Table 13-27 SNMP Power Messages used in CenturyLink
™
Chapter 13
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SEVERITY SNMP Trap Message Description
Major acFailure
PR001 - PR005
Major
Minor batteryOndischarge boostOn
Critical communicationLost
Major FuseFailure
Critical PR042 - PR062
Major
Minor
PR072 - PR092
PR093 - PR113
Critical PR135 - PR152
Major PR153 - PR170
Minor PR171 - PR185
Critical lowBattery
Major
Minor powerMajor
Minor/Major PR021 - PR041
Minor
Major
Minor
Minor
Major
Major powerMinor
PowerShed
MS441 - MS450 surgeArrestor
PR006 - PR010
PR011 - PR015
PR016 - PR020
EN081 - EN090 commercial AC power failure batteries on discharge batteries are on boost/equalize charge communication lost to the controller fuse blown power distribution alarm relay rack fuse alarm battery is in a discharged state generic power major generic power minor rectifier fail some loads have been shed in order to lengthen POTS battery backup toll ring generator alarm
TVSS/SPD failure generator run generator fail to start
Major
Major
Major
Major
Major
Major
PR114 - PR134 upsBypass transfer switch fail fuel tank alarm inverter (DC-to-AC converter) fail
UPS is on bypass upsBypassacabnormal UPS is on bypass due to poor AC quality from the inverter upsBypassacnormal upsBypassFreFail
Critical upsDischarged
UPS is on bypass, but the inverter is working properly
UPS failed to enter bypass due to failure to sync on frequency
UPS battery is discharged
Critical upsDiagnosticsFailed UPS self-check failed
Critical upsOnBattery
Critical upsOverload
Major
Major
Major
Major
Major
Major
Major upsRebootStarted upsRecRoterror upsScheduleShutdown the UPS is in a scheduled shutdown upsSleeping upsTemp upsTest upsTurnedOff
UPS battery on discharge
UPS is overloaded
UPS reboot started upsRecroterror the UPS is in sleep mode high temperature alarm on the UPS
UPS is in test mode
UPS has been turned off
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Chapter 14
Detail Power Engineering Checklist
CONTENTS
Chapter and Section Page
14. Detail Power Engineering Checklist ..................................................................... 14-1
14.1 Scope .............................................................................................................. 14-1
14.2 Detailed DC Power Engineering Audit .................................................... 14-1
14.3 Check List ...................................................................................................... 14-1
14.3.1 Power Plants ............................................................................... 14-1
14.3.2 Batteries ....................................................................................... 14-3
14.3.3 What Cable Racking is Required? ........................................... 14-4
14.3.4 How Much Cable is Piled on the Rack and is it Blocked? .... 14-4
14.3.5 Floor Loading of Equipment .................................................... 14-4
14.3.6 Converter Plants ......................................................................... 14-4
14.3.7 Ringing Plants............................................................................. 14-4
14.3.8 AC Equipment ............................................................................ 1454
14.3.9 Standby Engine Alternator ....................................................... 14-5
14.3.10 Lighting ....................................................................................... 14-5
14.3.11 Battery Distribution Fuse Boards (BDFBs) ............................. 14-6
Tables
14-1 BDFB Capacity Table ................................................................................................ 14-6
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14. Introduction
Chapter 14
Detail Power Engineering Checklist
14.1 Scope
This Chapter provides a procedure for auditing Power Plants in order to add or modify equipment. Depending on the scope of the job requested by the CenturyLink ™
Engineer, only portions of this may be necessary.
14.2 Detailed DC Power Engineering Audit
This Section provides a check list for performing an audit on power plants and their associated equipment. When using this check list, an “overview” inventory of the site
(using the forms in Chapter 15) may also be helpful. Copies shall be made available for the CenturyLink ™ Engineers and the local Power Maintenance Engineer.
14.3
Check List
14.3.1. Power Plants
14.3.1.1.
What type of power plant and the Manufacturer? (111A, 153, 154,
155, 302, 326, Lineage 2000 MCS, 1231H, 1231V, GPS, etc.)
14.3.1.1.1. What is the model?
14.3.1.1.2. If it is a WECO type plant is it a bus bar plant?
14.3.1.1.3. Does the plant have main term bars (a “chandelier”)?
14.3.1.2.
14.3.1.3.
14.3.1.4.
14.3.1.5.
14.3.1.6.
PBD location?
Power Plant voltage, (-48, ±24, ±130V)?
What type of controller does the power plant have?
How many PBD bays?
How many cables (and their sizes) are there feeding each PBD bay?
14.3.1.6.1.
Bay number 1
14.3.1.6.2.
Bay number 2
14.3.1.6.3.
Bay number 3
14.3.1.6.4.
Bay number 4
14.3.1.7.
List available fusing/circuit breaker locations, and sizes on plant.
14.3.1.7.1.
Fuse/CB number, PBD number
14.3.1.7.2.
Fuse/CB number, PBD number
14.3.1.7.3.
Fuse/CB number, PBD number
14.3.1.7.4.
Fuse/CB number, PBD number
14.3.1.8.
Where is the plant main shunt located (if there is one)?
14.3.1.8.1. Status of the main plant chandelier (if there is one)?
14.3.1.8.1.1.
Where is the chandelier located?
14.3.1.8.1.1.1.
What size is the chandelier bus bar (physical crosssectional dimensions and laminations, or ampacity)?
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Are there enough connections available for rectifier(s), battery string(s), and PBD additions?
14.3.1.10.
What is the drain on the power plant?
14.3.1.10.1.
Plant meter reading.
14.3.1.10.2.
PSMC reading (if there is one).
14.3.1.10.3.
What is the reading of the main power plant shunt in millivolts?
14.3.1.10.4.
What is the millivolt and Ampere rating of the main shunt?
14.3.1.11.
How many rectifiers are in the plant now?
14.3.1.11.1.
What type, model number, and current output?
14.3.1.11.2.
Rectifier nameplate AC input Amps, voltage, and phases (1 or 3)
14.3.1.11.3.
Where are rectifiers fed from: PDSC or main AC power board?
14.3.1.11.3.1. If it is from a PDSC what type, ampacity rating and what size of circuit breaker feeds it?
14.3.1.11.3.2. Is the peak load of the rectifier(s) fed by each individual
PDSC or HSP breaker/fuse ≤ 80% of the protector size?
14.3.1.11.3.3. For plants with an ultimate size of 2400 A or greater, are the rectifiers split up between 2 or more PDSCs?
14.3.1.11.3.4. Are there spare breaker positions to feed more rectifiers; if so write down the make and model # of the existing breaker/fuse and check to ensure they are still available?
14.3.1.11.4.
Are the rectifiers operational, (do they turn on)?
14.3.1.11.5.
Each rectifier ammeter reading.
14.3.1.11.5.1.
Rectifier G1
14.3.1.11.5.2.
Rectifier G2
14.3.1.11.5.3.
Rectifier G3
14.3.1.11.5.4.
Rectifier G4
14.3.1.11.5.5.
Rectifier G5
14.3.1.11.5.6.
Rectifier G6
14.3.1.11.5.7.
Rectifier G7
14.3.1.11.5.8.
Rectifier G8
14.3.1.11.5.9.
Rectifier G9
14.3.1.11.5.10.
Rectifier G10
14.3.1.12.
Is there a PSMC monitoring system existing; if so name type?
14.3.1.12.1.
How many available points?
14.3.1.12.2.
List of analog points?
14.3.1.12.3.
List of binary points?
14.3.1.12.4.
Is CO equipment intranet ethernet available?
14.3.1.12.5.
Have all alarms been tested and confirmed by the alarm center?
14.3.1.12.5.1.
If yes what is the log number?
14-2
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Issue K, July 2015
14.3.1.13.
What type of equipment does the power plant feed?
14.3.1.13.1.
IOF/Toll/Transport?
14.3.1.13.2.
Isolated ground plane Switch?
14.3.1.13.3.
Both?
Chapter 14
Detail Power Engineering Checklist
14.3.1.13.4.
If ESS ™ is it 5E, DMS ™ , or Ericsson?
14.3.1.14.
Where is the ground window (if an ESS ™ or shared plant)?
14.3.1.14.1.
Is the ground window also the plant return bar?
14.3.1.14.2.
Is the ground window a remote ground window?
14.3.1.14.3.
Can the ground window be grown?
14.3.1.14.4.
How many positions are available on the:
14.3.1.14.4.1.
Integrated side?
14.3.1.14.4.2.
Isolated side?
14.3.1.14.5.
How many and what size of cables are powering the ground window MGB bar(s) if it is doubling as the plant return bar?
14.3.1.14.6.
If bar feeds distribution, can distribution be rerun to BDFB(s)?
14.3.1.15.
Is the frame grounding of power bays and battery stands adequate?
14.3.1.16.
Location of Power equipment
14.3.1.16.1.
Is there physically enough room to add it?
14.3.1.16.2.
Is it the best location?
14.3.1.16.3.
Are there overhead obstructions?
14.3.1.16.4.
What is the closest distance to equipment being fed?
14.3.1.16.5.
Are there problems getting AC input to rectifier PDSCs?
14.3.1.16.6.
Check aisle depth vs. NEC requirements for AC-fed gear.
14.3.2.
Batteries
14.3.2.1.
14.3.2.2.
How many battery strings are there in the plant now?
What type and size, (MCT II 4000, LCT1680, GU45, FTC21P,
KS20472L1S etc.), and installation date for each string?
14.3.2.2.1.
String A
14.3.2.2.2.
String B
14.3.2.2.3.
String C
14.3.2.2.4.
String D
14.3.2.2.5.
String E
14.3.2.2.6.
String F
14.3.2.2.7.
String G
14.3.2.2.8.
String H
14.3.2.2.9.
String J
14.3.2.3.
14.3.2.4.
14.3.2.5.
Is each battery string equipped with shunts?
What are the types of battery stands?
What cabling is needed to meet voltage drop for new stands?
14-3
Chapter 14
Detail Power Engineering Checklist
14.3.3.
What cable racking is required?
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Issue K, July 2015
14.3.3.1.
14.3.3.2.
14.3.3.3.
14.3.3.4.
14.3.3.5.
Ceiling height?
Is there any existing superstructure?
Will two levels of framing be required?
What types of connections are required to ceiling? (Ceiling inserts, or imbedded Uni-Strut™?)
If there is no existing superstructure, can everything be supported from the floor?
Are there obstructions such as air vents/duct, pipes etc.? 14.3.3.6.
14.3.3.6.1.
No water pipe is directly above power equipment?
14.3.3.7.
14.3.3.8.
Is there proper sway bracing for E/Q zone if applicable?
Is there separate fused and unfused cable racking?
14.3.4.
How much cable is piled on the rack and is it blocked?
14.3.4.1.
Are cable holes full?
14.3.5.
Floor loading of equipment.
14.3.6.
Converter Plants
14.3.6.1.
14.3.6.2.
14.3.6.3.
14.3.6.4.
14.3.6.5.
14.3.6.6.
14.3.6.6.1.
What size is the fusing feeding the converters?
14.3.6.7.
14.3.6.8.
14.3.6.9.
What is the location of the converter plant?
What is the model number of the converter plant?
Who is the manufacturer of the converter plant?
What is the voltage of the converter plant? (±24V, ±130V, etc.)
What is the load on the converter plant?
What is the feeding power plant?
What are the quantities and sizes of the converters?
Identify the existing loads on the converter plant distribution, and spare positions.
Is the converter plant properly grounded and ground-referenced
14.3.7.
Ringing Plants
14.3.7.1.
14.3.7.2.
14.3.7.3.
14.3.7.4.
What is the location of the ring plant?
What is the model number of the ring plant?
Who is the manufacturer of the ring plant?
What is the feeding power plant?
14.3.7.5.
What is the ring generator model number?
14.3.7.5.1.
How many ring generators are there?
14.3.7.6.
What is the tone generator model number?
14-4
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Issue K, July 2015
14.3.7.7.
14.3.7.8.
14.3.7.9.
Chapter 14
Detail Power Engineering Checklist
What is the interruptors’ model number?
Identify existing loads on the ring plant distribution, and spare positions
Is the ring plant properly grounded and ground referenced?
14.3.8.
AC Equipment
14.3.8.1.
What is the AC voltage and phases available at the main HSP?
14.3.8.1.1.
208V, 240V, or 480V, and single or three-phase?
14.3.8.2.
14.3.8.3.
14.3.8.4.
14.3.8.5.
14.3.8.6.
14.3.8.7.
14.3.8.8.
14.3.8.9.
What are the voltage and current readings at the HSP?
Can the HSP be added to safely?
Where does one go to get AC to power the rectifier(s)?
Are rectifiers powered from a step up or down transformer?
What is the circuit breaker or fuse size for the main AC entrance?
What is the cable size of the HSP conductors?
What is Ampere rating of the House Service Panel?
What is the transformer from the utility company rated at (kVA)?
14.3.8.10.
What is the make and model of the transfer switch?
14.3.8.11.
What is the make, model, rating, and load of the existing inverter and/or UPS?
14.3.8.12.
Identify existing inverter/UPS distribution.
14.3.8.13.
Is the AC equipment properly bonded and grounded?
14.3.9.
Standby Engine-Alternator
14.3.9.1.
14.3.9.2.
14.3.9.3.
14.3.9.4.
14.3.9.5.
14.3.9.6.
14.3.9.7.
14.3.9.8.
What was the load and date at the last engine run?
What is the kW rating of the standby set?
What is the size and type (above-ground, vaulted, etc.) of the main fuel tank?
What type of fuel does the standby set use (diesel, gas, propane)?
What is the engine start battery’s model and installation date?
What is the Battery charger size and type?
Is there a fuel tank monitor?
Is the Engine room/enclosure and tank properly bonded and grounded?
14.3.10.
Lighting
14.3.10.1.
Is there DC task lighting available per Chapter 12?
14.3.10.2.
Is there low level AC lighting in place in the power areas?
14.3.10.3.
Is any lighting required for added equipment?
14.3.10.3.1.
Where is power available to add lighting, and is it 120 or 277V?
14-5
Chapter 14
Detail Power Engineering Checklist
14.3.11.
Battery Distribution Fuse Boards (BDFBs)
PUB 77385
Issue K, July 2015
14.3.11.1.
Is there physically enough room to add a BDFB?
14.3.11.2.
Is the planned location for the BDFB the best location?
14.3.11.3.
Are there overhead obstructions, both above the BDFB for potential cable entrance and return bars, and in the primary cable rack path?
14.3.11.4.
What is the closest distance to the equipment being fed?
14.3.11.5.
Are there available fuse positions and return bus positions in the existing BDFB?
14.3.11.5.1.
Are the fuse assignments records updated for the BDFB?
14.3.11.5.2.
If the BDFB is out of return bus positions, can it be expanded?
14.3.11.6.
Complete Table 14-1 for each BDFB. ( Note: There should be a minimum of 2 and a maximum of 8 feeder fuses for each BDFB)
14.3.11.6.1.
If the load is greater than half the feeder fuse capacity for any
BDFB, that BDFB must be immediately embargoed for growth, an MR must be generated by the Power Maintenance Engineer, and a direct call must be made to engineering to address the problem. If this is the case for any BDFB/BDCBB or dual load miscellaneous fuse/breaker panel, can any of the loads be transitioned to relieve the burden?
14.3.11.6.2.
What is the make, model, and RR # of the existing BDFB?
14.3.11.6.3.
Is there dedicated power rack at the BDFB?
Table 14-1 BDFB Capacity Table
BDFB LOCATION:
A FEEDER
B FEEDER
C FEEDER
D FEEDER
Feeder Fuse
Location
Fuse Capacity
Load Reading at
BDFB or PBD
14-6
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Issue K, July 2015
Chapter 15
Turn Up, Test and Acceptance Procedures
CONTENTS
Chapter and Section Page
15. Turn Up, Test and Acceptance Procedures .......................................................... 15-1
15.1 General ........................................................................................................... 15-1
15.2 Maintenance Window Guidelines for Power .......................................... 15-1
15.3 Forms .............................................................................................................. 15-3
Forms
820 Generic Test and Acceptance Checklist ................................................................. 15-4
821A Power Room Lighting Test and Acceptance Checklist ....................................... 15-5
821B Alarm and/or Power Monitor/Controller (PSMC) Test and
Acceptance Checklist ................................................................................................ 15-6
821C BDFB, Power Board, or Fuse Panel Test and Acceptance Checklist .................. 15-7
822 Batteries and Stands Test and Acceptance Checklist ........................................... 15-8
823A Rectifier Test and Acceptance Checklist ................................................................ 15-9
823B Power/Battery Plant Test and Acceptance Checklist ........................................ 15-10
824A Converter Plant Test and Acceptance Checklist ................................................. 15-11
824B Residual Ring Plant Test and Acceptance Checklist .......................................... 15-12
825A Inverter Test and Acceptance Checklist .............................................................. 15-13
825B UPS Test and Acceptance Checklist ..................................................................... 15-14
826A Standby Engine Test and Acceptance Checklist ................................................. 15-15
826B Transfer System and AC Service Entrance Test and Acceptance Checklist ... 15-16
826C Fuel Tank, Fuel System, and Fuel Monitor Test and Acceptance Checklist .. 15-17
827 RT/Prem Site Test and Acceptance Checklist .................................................... 15-18
828A Building Grounding Test and Acceptance Checklist ......................................... 15-19
828B Power Distribution Bus Bar Test and Acceptance Checklist ............................ 15-20
829A Power Area Floor Plan Test and Acceptance Checklist .................................... 15-21
829B Power Documentation Test and Acceptance Checklist ..................................... 15-22
840 Power Equipment Inventory ................................................................................. 15-23
841 BDFB/PBD Panel Fuse/Breaker Assignment Record ....................................... 15-24
844 Critical Larger Site Power Alarm Verification .................................................... 15-25
845 Smaller Site Power Equipment Inventory ........................................................... 15-26
846 Smaller Site Housekeeping Alarm Verification .................................................. 15-27
TOC 15-i
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Issue K, July 2015
15. Turn Up, Test and Acceptance Procedures
15.1 General
Chapter 15
Turn Up, Test And Acceptance
The attached forms are for use in all types of sites for performance of power turn up, test, and acceptance. The forms are self-explanatory, with listings for notes, functions, and supporting documentation. Supporting documentation for the functions will vary by site because there are many different manufacturers for each type of equipment.
Copies of most of these forms can also be found in CenturyLink ™ Technical Publication
77350. Three copies of each form shall be made; one shall be left on site with the job package, one shall be sent to the CenturyLink ™ Engineer, and one shall be sent to the local CenturyLink ™ Power Maintenance Engineer for that state. Note that the forms do not start with Form number 1. This is due to the fact that the forms originate from an internal CenturyLink ™ power maintenance document, and in order to ensure that contracted installers and CenturyLink ™ technicians are using the same form for the same activity, the form numbers of that document have been retained.
The installation provider is responsible for verifying that all the alarms are reporting correctly to the proper alarm center. The installer must call the alarm center and ask them whether an alarm has been generated, and whether the names(s) of the alarm(s) generated correspond(s) to the alarm the installer initiated. The installer shall then note the center response on the proper form(s).
15.2 Maintenance Window Guidelines for Power
A Maintenance (Installation) Window is a predetermined period during each day when specific planned maintenance and infrastructure provisioning work activities should be performed. The purpose of scheduling work during specific times is to ensure a minimal amount of disruption to CenturyLink ™ customers. Although load and service conditions vary by site, nighttime is generally the time of least traffic in most
CenturyLink ™ sites. Therefore the official Maintenance Window is:
Monday to Friday 10:00 p.m. to 6 a.m. (12 am to 5 am for work that could affect video)
Saturday 10 p.m. to Monday 6 a.m. (12 am to 5 am for work that could affect video)
For work that could affect DSL circuits, the Maintenance Window is midnight to 6 a.m.
Sunday through Thursday
If in doubt, almost all Power work that involves even the slight possibility of taking down equipment should be done in the Maintenance Window to be safe, because nothing works without Power. However, because local conditions for each site are more likely to be known locally, the final decision is left up to the local managers.
15-1
Chapter 15
Turn Up, Test And Acceptance
The following maintenance items should almost always be performed in the
Maintenance Window:
PUB 77385
Issue K, July 2015
• Battery Discharge tests of single string plants
• Building Power Blackout tests (annual engine run)
The following Power and Grounding Installation/Removal activities must be performed in the Maintenance Window. These generally only apply to in-service or
"hot" equipment, or the specific times when "dead" equipment is being connected to
"live" equipment. Power and Grounding Installation Guidelines are contained in
Chapters 8, 9, and 10 of CenturyLink ™ Technical Publication 77350.
• Any disconnections from the Ground Window MGB, CO Ground Bars, or main
Horizontal or Vertical Equalizers while they are "in-service" should normally be
Maintenance Window work
• Any connections or disconnections to the hot bus bars should almost always be done in the Maintenance Window (turning on a breaker or inserting a fuse/fuseholder does not require manual or tool touching of a hot bus, and therefore, may be done outside of the Maintenance Window; however, although connection of cables to "dead" fuse or breaker positions on the rear is not technically "hot", there are nearby hot buses, which may merit consideration for moving that work to the Maintenance Window)
• Any addition or removal of batteries from "live" strings (although it's desirable to do all this work in the Maintenance Window, it's only absolutely required for single string plants)
• Any connection or disconnection on the main AC power Board (feeder side) or any work on the AC transfer switch (see the exception above for the insertion of breakers) should be done in the Maintenance Window
Remoter locations (e.g., RT Cabinets, CEVs, huts, Customer Premises, etc.) deserve special Maintenance Window consideration due to access, lighting, and affected customers. Note that, in all cases, the final decision is up to the local manager. These managers also sign installation MOPs (even though Pub 77350 is geared towards CO work, the MOP process is recommended for RT/Prem sites as well; especially Customer
Premises sites, as per Pub 77368). Some guidelines for RT/Prem Power work, from
NROC Power Tech Support, follow. They apply to installation and maintenance activities described above, but modified by the following paragraphs.
• RT/Prem sites/equipment with less than 96 DS-0 (POTS) customers (equivalent to 4 or less T1s), might usually be exempted from the power Maintenance
Window. SHARP/SHNS and other guaranteed services should usually follow the Maintenance Window, due to significant customer refunds for outages.
15-2
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Issue K, July 2015
Chapter 15
Turn Up, Test And Acceptance
• For RT cabinets, night work may not be feasible in all cases (although small jobs may be done by flashlight or headlamp); due to the disruption that lighting, running trucks, generators, etc. can cause in neighborhoods. In some neighborhoods, for some "planned" activities (especially routine maintenance), night work may cause more customer ill will than it prevents
• For outdoor DSL cabinets, in cases where lighting, noise, etc. can be issues, as described above, the Maintenance Window may be extended to 8 a.m. with the permission of the local manager.
• Customer Premises installations are supposed to allow us 7 x 24 access, but this doesn't always happen. For Customer Premises that allow 7 x 24 access,
Maintenance Window guidelines should generally be followed due to the HiCap circuits/services usually located there. Any Customer Maintenance Window should supersede our own (coordinate with them).
• Controlled environment electronic equipment enclosures (EEEs) include CEVs,
CEC ™ s, huts, UE ™ s, etc. generally have fiber, and/or enough POTS customers to warrant Maintenance Window guidelines being followed.
15.3 Forms
15-3
Chapter 15
Turn Up, Test And Acceptance
CenturyLink ™
GENERIC TEST & ACCEPTANCE CHECKLIST
PUB 77385
Issue K, July 2015
Site:
Engineer:
Date of Installation completion:
Tested by:
Job Number BVAPP:
Job Number Vendor:
Date of Vendor Departure:
Date:
ITEM
Equipment Verification
Frames located per floor plan
Installed per drawings
Equipment is what was ordered
Equipment options are correct
Spare equipment provided per ordering spec (if applicable)
Power feed to equipment checked
Workmanship
Frame alignment and equipment mounting
Relay rack numbering
Wiring and cabling (including tagging of unused cables)
Equipment numbering and lettering
Cable openings sealed
Cable racks and other ironwork
Power and fusing (spare fuses available also)
Combustible materials removed from network eqpt areas (especially power areas)
Performance Tests
Tests per recommended equipment manual
Tests per Test & Acceptance package sent out with job
Documentation
"As-built" drawings sent back to engineering
Replacement drawings left on site
Initial battery charge reports (if applicable)
Equipment manuals received
Original test results retained
Alarms
Affected alarms tested prior to work start
Local and audible alarms (as applicable) tested prior to work start
Other
Alarms installed and tested with Alarm Center
Name of NROC Center Contact with whom alarms were tested:
Comments (all No answers must be commented on)
YES
NO
Form 820 Generic Test and Acceptance Checklist
15-4
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Issue K, July 2015
Chapter 15
Turn Up, Test And Acceptance
CenturyLink ™
POWER ROOM LIGHTING TEST & ACCEPTANCE CHECKLIST
Site:
Engineer:
Date of Installation completion:
Tested by:
Job Number BVAPP:
Job Number Vendor:
Date of Vendor Departure:
Date:
ITEM
1. Lighting provided in the power areas is adequate, and located in accordance with the site record lighting plan drawing
2. As a minimum, emergency/stumble lighting is available in stairwells; and task lighting over the control PBD, over the engine control panel and AC transfer system, over the main AC switchgear, and in the engine room
3. Emergency egress/stumble and task lighting works
4. Feeding fuse/breaker positions and emergency egress/stumble and task lighting fixtures are properly stenciled as to the equipment they feed or where they are fed from
Test & Acceptance should be performed with the installer on site.
Note below all problems they fix:
Comments (all No answers must be commented on)
YES NO
Form 821A Power Room Lighting Test and Acceptance Checklist
15-5
Chapter 15
Turn Up, Test And Acceptance
CenturyLink ™
ALARM AND/OR POWER MONITOR/CONTROLLER (PSMC)
TEST & ACCEPTANCE CHECKLIST
PUB 77385
Issue K, July 2015
Site:
Associated Power Plant:
Engineer:
Date of Installation completion:
Tested by:
Job Number BVAPP:
ANTS/PNAR #:
Job Number Vendor:
Date of Vendor Departure:
Date:
ITEM
1. Complete copy of suppliers' manuals and drawings available on site
2. Verify accuracy of the database, and ensure an electronic backup is made where applicable
3. Verify that analog channel readings are within 1% of the values measured by plant meters or by technician's hand-held meter
4. Bring in each binary alarm associated with this monitor (or other alarming device) and verify that technicians in the NOC receive the alarm
A. There is local indication of the alarm on the monitor, if monitor is capable of this function
B. If monitor is capable and equipped, verify the difference between Minor Rectifier Fail
(1 rectifier), and Major Rectifier Fail (2 or more rectifiers failed)
5. Bring in binary alarms associated with the threshold settings of analog points (e.g., low voltage, etc.), and ensure that these alarms report locally on the monitor and remotely to the NOC
A. Analog points' binary thresholds are set properly (according to Chapter 13)
6. If the monitor is controlling High Voltage Shutdown (HVSD), verify proper operation
7. Ensure that all binary, analog, & control points requested on the job were provided, and ensure that there is a record left in the office on paper and/or on disk of the assignments
8. Verify the difference between Minor Converter Fail (1 converter), and Major Converter Fail (2 or more converters failed)
9. Verify security levels (e.g., different passwords), and dial-back numbers (if applicable)
10. Verify that the system reboots properly after being turned off/on
11. Verify through NOC, continuity of X.25 and/or IP link as applicable
12. When monitor is equipped with control functions, verify proper operation of these functions
(e.g., ring transfer, etc.)
13. Verify that a laptop can communicate with the monitor over an RS-232 port
14. Note the number of spare analog and/or binary points, and report them to Engineering
15. Verify communication with the unit over a dialup modem
Test & Acceptance should be performed with the installer on site. Note below all problems they fix
YES NO
NOTE 1: Use supplier, Telcordia ® , and CenturyLink ™ documentation as a guide to performing the tasks above.
NOTE 2: When testing alarms and functions, be sure not to interrupt service unless absolutely necessary, and done during the Maintenance Window with notification to and signoff from appropriate personnel
Comments (all No answers must be commented on)
Form 821B Alarm and/or Power Monitor/Controller (PSMC) Test and Acceptance
Checklist
15-6
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Issue K, July 2015
Chapter 15
Turn Up, Test And Acceptance
CenturyLink ™
BDFB, POWER BOARD, OR FUSE PANEL
TEST & ACCEPTANCE CHECKLIST
Site:
Engineer:
Power Board &Fuse Numbers
Date of Installation completion:
Tested by:
Job Number BVAPP:
Job Number Vendor:
BDFB Location
Date of Vendor Departure:
Date:
ITEM
1. Proper equipment was ordered and is sized appropriately for the application
2. Verify proper load bus arrangements by ensuring only 1 bus is hot with each feeder breaker on or fuse inserted
3. Verify proper return bus options
4. Verify accuracy & proper operation of the digital or analog meters & current shunts
5. Test fuse alarms for proper operation and continuity to the appropriate NOC
6. Verify proper placement, anchoring, and stenciling of the bay(s) and/or shelves
7. Ensure that all fuse/breaker assignments are properly marked/stenciled (including fuse size) for the loads they feed, and that all incoming and outgoing cables are properly tagged
8. Verify proper connections (including irreversible Listed crimps, and anti-oxidant of wires/cables to the distribution, ground, and battery return buses/connections
9. Verify proper cable routing
10. Verify proper frame and site grounding
11. Report the number and type of spare fuse/breaker positions to Engineering
12. Ensure that BDFBs are equipped with a sticker(s) specifying the maximum feeder load (50% of the protector size) for each feeder
13. Ensure all positions (including unused) are labeled for position #, that the bay is marked with its PBD/RR location, and that the shelves are labelled
14. Ensure dummy fuses, holders, or covers installed in positions that require it
YES NO
Test & Acceptance should be performed with the installer on site. Note below all problems they fix
NOTE: Use supplier documentation as a guide to performing the tasks above.
NOTE: Work on a Power Board or BDFB has the potential to interrupt service. Service shall not be interrupted when installing primary or secondary distribution panels. Cutover of a BDFB or Power
Board should probably occur during the Maintenance Window if the power plant is already up and supporting loads.
Comments (all No answers must be commented on — use the back of this form if necessary)
Form 821C BDFB, Power Board, or Fuse Panel Test and Acceptance Checklist
15-7
Chapter 15
Turn Up, Test And Acceptance
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Issue K, July 2015
CenturyLink ™
BATTERIES & BATTERY STANDS TEST & ACCEPTANCE CHECKLIST
Site:
Associated Power Plant:
Engineer:
Date of Installation completion:
Tested by:
Job Number BVAPP:
Battery String #:
Job Number Vendor:
Date of Vendor Departure:
Date:
ITEM YES NO
1. Battery stands & batteries marked with install and mfg date (on batteries), string
#s/letters, voltage match colors (if applicable) & cell #s (not required for 6/12 V).
2. Batteries and connectors are free of the following defects.
A. Cases crazed, cracked, bulged, corroded, or leaking
B. Level indicators missing or incorrect (for flooded batteries only)
C. Cover or post rise, and/or post corrosion
D. Excessive positive plate growth or strap growth for flooded cells with clear jars
E. Excessive plate bowing or cracking for flooded cells with clear jars
F. Excessive needle growth for flooded cells with clear jars
G. Lead-sulfate crystals for flooded cells with clear jars (check after initial charge)
3. Electrolyte level proper, & limits for electrolyte level are marked on wet cells.
4. Proper wet cell vent/fill caps installed, & flame arrestors have dust covers.
5. Battery records/logs and any manufacturer documentation is on-site and easily accessible. The Storage Battery report (RG47-0001) should have been filled out by the installation vendor for flooded cells.
6. Neutralizing agents and protective equipment are available nearby for use as required in the battery area: eyewash, absorbent pillows, neutralizer, rubber gloves, goggles, rubber apron. (This requirement is only applicable in buildings).
7. Thermometers and/or temperature probes are installed as required.
8. Check batteries and intercell connection integrity by placing string on a 5-minute discharge test into a real load or load box. (This requirement is optional if the string is installed into a new plant with no real load. At a minimum, attempt to determine if connections were properly tightened with a torque wrench.).
9. All flooded battery 1.215 s.g. cell voltages are above -2.14 on float.
10. Batteries and connections (irreversible Listed crimps for lugs) are properly marked, coated with a thin film of anti-oxidant, and connected to +/-.
11. Temperature compensation employed and working with VRLA batteries
12. Spill containment (room/area or individual stand) installed for new flooded batteries in plants with at least 4 strings of 1680 Ah or 2 strings of mini-tanks
13. Disconnects (if used) sized per Chapter 3; & wired to remote trip only if required.
14. Battery stand is braced appropriately for earthquake zone in which site is located.
15. Proper warning labels installed on/near stands and on room door.
16. Batteries appear to be sized to provide appropriate reserve per this Tech Pub.
Test & Acceptance should be performed with the installer on site. Note on back all problems they fix.
Comments (all No answers must be commented on —additional room on back) reference Routines EE200, EE201, EE202, EE757, EE758, EE759, EE660, and EE720
Form 822 Batteries and Stands Test and Acceptance Checklist
15-8
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Issue K, July 2015
CenturyLink ™
RECTIFIER TEST & ACCEPTANCE CHECKLIST
Chapter 15
Turn Up, Test And Acceptance
Site:
Rectifier #’s:
Engineer:
Date of Installation completion:
Tested by:
Job Number BVAPP:
Associated Power Plant:
Job Number Vendor:
Date of Vendor Departure:
Date:
ITEM
1. Rectifiers are properly assembled, installed, and stenciled or identified.
2. Correct type & capacity fuses are provided, & all fuses are clean & properly installed.
3. AC power connections are properly made and labeled for feeder breaker location.
Ensure proper transformer taps and phase rotation where applicable.
4. Ensure that correct rectifier (size, type, AC input, etc.) was ordered, including correct wiring or apparatus options.
5. Rectifiers operate per individual operation tests, and basic operational features work.
6. Rectifier and/or Plant meters are accurate and properly adjusted.
7. Alarm settings are adjusted to requirements, and proper alarm signals are transmitted
8. Current limiting and partial load features of units are set and adjusted properly.
9. High Voltage shutdown (HVSD) feature operates properly, and all other DIP switches, potentiometers, and other options are properly set, including alarm thresholds.
10. Outputs of all units are stable (non-hunting, except for load sharing variations), & rectifier float voltages are properly set for battery type (see Chapter 13) & load sharing
11. Simulate an AC power failure to verify that the units' auto-restart capability and current walk-in feature operate properly when AC power is restored. Ensure also that alarms clear and that the units return to float voltage.
12. All rectifiers are capable of operating, regulating, and current limiting at full load.
13. Ensure AC fuse/breaker panel(s) feeding rectifiers have adequate spare capacity.
14. For multi-phase fed rectifiers, verify appropriate operation or shutdown during phase failure if possible.
15. Ensure proper selection and routing of rectifier control cables to plant controller.
16. Ensure rectifier frames are properly grounded & that battery return cables are properly grounded & sized, dependent on whether plant is integrated, isolated, or combined.
17. Ensure rectifier DC output cables are properly installed, & sized according to Chapter 2
(for 200 and 400 Amp rectifiers), or manufacturers’ recommendations (all other sizes).
18. If the plant load exceeds the smallest rectifier size, ensure that each rectifier will carry full-rated load for at least 1 minute. Ensure that there is at least n+1 redundancy and a minimum of 120% (125% for VRLAs) total rectifier capacity compared to float load.
19. Ensure that there is adequate ventilation & heat dissipation so rectifier will not overheat.
YES
NO
Test & Acceptance should be performed with the installer on site. Note below all problems corrected
NOTE: When testing alarms and functions, be sure not to interrupt service. Consider whether it is required to perform any of the tests in the Maintenance Window.
Comments on back of form (all No answers must be commented on)
Form 823A Rectifier Test and Acceptance Checklist
15-9
Chapter 15
Turn Up, Test And Acceptance
PUB 77385
Issue K, July 2015
CenturyLink ™
POWER/BATTERY PLANT TEST & ACCEPTANCE CHECKLIST
Site:
Power Plant:
Engineer:
Date of Installation completion:
Tested by:
Job Number BVAPP:
Location:
Job Number Vendor:
Date of Vendor Departure:
Date:
ITEM YES NO
1. All battery distribution cables are of correct size and type, and properly terminated
2. All equipment of control and distribution bays are correctly stenciled or identified
3. All control circuit, charge, and discharge fuses and/or circuit breakers are of the correct type and capacity, and located as shown on the drawings
4. Alarm fuse positions are equipped with correct fuses, and fuse and circuit breakers are properly designated as to the equipment they serve
5. Verify alarms, locally, and to the Alarm Center
6. All DC meters are calibrated and properly adjusted
7. All fuses are tight in their respective fuse holders, and fuses and circuit breakers are free of excessive heat
8. The battery float voltage is correct (check after meter calibration, and initial charging of the batteries)
9. The voltage alarm settings are correct per Chapter 13
10. Spare fuses are provided, and properly located & designated, near the battery plant
11. If LVD is used (use only where required), ensure setting is -43.25 V or less.
12. Power bays are properly labeled for PBD/RR position
Test & Acceptance should be performed with the installer on site. Note below all problems they fix
Comments (all No answers must be commented on)
Form 823B Power/Battery Plant Test and Acceptance Checklist
15-10
PUB 77385
Issue K, July 2015
CenturyLink ™
CONVERTER PLANT TEST & ACCEPTANCE CHECKLIST
Chapter 15
Turn Up, Test And Acceptance
Site:
Associated Power Plant:
Engineer:
Date of Installation completion:
Tested by:
Job Number BVAPP:
Location:
Job Number Vendor:
Date of Vendor Departure:
Date:
ITEM
1. The converter plant is properly assembled and installed (including properly made electrical connections), and stenciled or identified
2. The input and output fuses are the correct type and capacity
3. The discharge fuse alarms are operative and connected properly, and spare fuses are available
4. The voltage alarm levels are properly adjusted to specified limits
5. All alarms function properly, and are received by the Alarm Center
6. High Voltage shutdown (HVSD) feature operates properly
7. The converter plant meters are accurate, and properly adjusted, and all other LEDs or other indicators work properly
8. The output voltage is adjusted within the specified limits, and can be accurately read from the test jacks
9. The output current limit is properly set, as well as any other options set through
DIP switches or potentiometers
10. Verify that the converter plant functions properly under load (preferably up to the n-1 capacity, and preferably off-line on a load bank) for at least 30 minutes, and that there are no problems if the converters are switched on and off.
YES NO
Test & Acceptance should be performed with the installer on site. Note below all problems they fix.
NOTE: When testing alarms and functions, be sure not to interrupt service unless done during off hours and with notification to appropriate personnel
Comments (all No answers must be commented on)
Form 824A Converter Plant Test and Acceptance Checklist
15-11
Chapter 15
Turn Up, Test And Acceptance
CenturyLink ™
RESIDUAL RING PLANT TEST & ACCEPTANCE CHECKLIST
PUB 77385
Issue K, July 2015
Site:
Associated Power Plant:
Engineer:
Date of Installation completion:
Tested by:
Job Number BVAPP:
Location:
Job Number Vendor:
Date of Vendor Departure:
Date:
ITEM YES NO
1. The ringing plant is properly assembled, installed, and stenciled or identified
2. Ringing plant fusing is in agreement with site drawings
3. All alarms operate properly, including transfer alarms and report to the NOC
4. The transfer feature operates automatically when a power failure occurs (for units when Ring Generator 1 is AC powered), or if Ring Generator 1 fails. (This transfer also applies to those sites equipped with interruptors besides the ring generators)
5. If equipped, the transfer feature operates properly by manual or test transfer
6. All voltages, tone levels, and frequencies are within specified limits
7. If meters are provided, they are accurate, and within adjustments
Test & Acceptance should be performed with the installer on site. Note below all problems they fix.
Comments (all No answers must be commented on)
Form 824B Residual Ring Plant Test and Acceptance Checklist
15-12
PUB 77385
Issue K, July 2015
CenturyLink ™
INVERTER TEST & ACCEPTANCE CHECKLIST
Chapter 15
Turn Up, Test And Acceptance
Site:
Associated Power Plant:
Engineer:
Date of Installation completion:
Tested by:
Job Number BVAPP:
Location:
Job Number Vendor:
Date of Vendor Departure:
Date:
ITEM
1. The inverter plant is properly assembled and installed (including proper electrical connections), and stenciled or identified (outlets and AC panels fed by the inverter should also be marked, and any AC voltage over 120 VAC nominal should be marked in red/vermilion if it appears at an outlet).
2. Input, output, and alarm fuses or breakers are the correct type and capacity, and output distribution is properly sized and connected
3. Simulate an AC power failure. Ensure proper operation and transfer. During outage, check output voltage and frequency.
4. Verify that plant is capable of operation at full load; in either AC input or DC input modes. (Use a dummy load — e.g., load box — if necessary to fully load the plant)
5. Verify proper operation of maintenance bypass, if equipped
6. Alarms operate to the Alarm Center and clear properly
7. Verify proper operation of any automatic shutdowns (e.g., low voltage, emergency. stop, etc.)
8. Verify proper operation of all controls and indicators (meters, LEDs, etc.)
9. Improper loads are not connected to expensive inverter power (see Chapter 5).
10. Ensure that a new ground reference is provided from a COGB or PANI MGB, and that neutral and ACEG are tied together at the output
11. Ensure there is adequate room and ventilation around the inverter plant
YES NO
Test & Acceptance should be performed with the installer on site. Note below all problems they fix.
NOTE: When testing alarms and functions, be sure not to interrupt service unless done during off hours and with notification to appropriate personnel
Comments (all No answers must be commented on)
Form 825A Inverter Test and Acceptance Checklist
15-13
Chapter 15
Turn Up, Test And Acceptance
CenturyLink ™
UPS TEST & ACCEPTANCE CHECKLIST
PUB 77385
Issue K, July 2015
Site:
Engineer:
Date of Installation completion:
Tested by:
Job Number BVAPP:
Job Number Vendor:
Date of Vendor Departure:
Date:
ITEM
1. UPS is properly assembled (including any filters), installed (including clearances & leveling, and in a proper air-conditioned and ventilated environment), & stenciled/identified
(including proper arc flash/blast labels) per Engineering instruction (outlets & AC panels
[including PDUs] fed by UPS should also be marked as “protected”, and any outlet providing more than nominal 120 VAC should be marked in red/vermilion)
2. The correct type & capacity fuses are provided, and all fuses are clean and properly installed
3. AC/DC power connections (including proper bolt torquing & washers) are made per
Engineering instructions, & in compliance with CenturyLink ™ Tech Pub 77350 and this one
4. Transformer taps are set properly (output voltage is within the proper range)
5. Ensure proper AC phase rotation on the output
6. Plant meters are accurate and properly adjusted
7. Alarm settings are adjusted to requirements, & proper alarm signals transmitted. Ensure that alarms reach the appropriate Alarm Center (and/or local terminal). The permanent battery monitor (if installed) is correctly installed and set up.
8. Correct wiring/apparatus provided & wiring is properly routed, supported & braced
9. Current limiting & partial load features of units set & adjusted per Engineering requirements
10. High voltage and EPO shutdown features operate properly
11. Outputs are stable (non-hunting, except for minor load sharing variations)
12. Simulate AC power failure to verify unit's auto-switch capability, and that it operates properly when AC power is restored (ensure that alarms clear when AC is restored). Ensure that it synchronizes/parallels with parallel UPS units/modules, if applicable; and shares load reasonably between modules/units. Ensure static/maintenance bypasses work too.
13. UPS works at full load for at least 1 hr (and handles step loads, as determined by steploading and de-loading in 25% increments), & a thermal scan under full load shows no problems. Verify UPS input/output THD is within specs during this test.
14. UPS normal load < 80% for a non-redundant UPS, or < 40% for redundant UPS setups
15. Battery chargers are operating at the required output voltage. A commissioning battery discharge test (including IR scan) was performed to ensure at least 90% of rated capacity?
16. Unit is properly grounded per NEC ® requirements, and doors/shelves/etc are bonded
17. Are detailed operating instructions posted at the hard maintenance bypass
YES NO
Test & Acceptance should be performed with the installer on site. Note below all problems they fix.
NOTE: Use supplier documentation as a guide to performing the tasks above.
NOTE: When testing alarms/functions, don’t interrupt service unless during off hours w/appropriate notification
Comments (all No answers must be commented on – use the back of this sheet as needed)
Form 825B UPS Test and Acceptance Checklist
15-14
PUB 77385
Issue K, July 2015
™
CenturyLink
STANDBY ENGINE TEST & ACCEPTANCE CHECKLIST
Chapter 15
Turn Up, Test And Acceptance
Site:
Engineer:
Date of Installation completion:
Tested by:
Job Number BVAPP:
Job Number Vendor:
Date of Vendor Departure:
Date:
ITEM
1. Engine-alternators & associated equipment are located according to the floor plan drawings, & are installed according to Engineering request, & are properly sized (e.g., fuel and exhaust system piping & tubing)
2. Engine start batteries and chargers are in good condition, and installed and operating properly
3. Verify start batteries and charger per Forms 822, 823A, & manufacturers’ documentation
4. A remote emergency stop button is located outside but near engine room, & is properly identified & alarmed
(for outdoor engine enclosures with the transfer switch indoors, there also needs to be a button indoors)5
5. Test records, logs, & mfg documentation on site (with combustibles in engine rm stored in a fireproof cabinet)
6. Before operation, inspect for the obvious, like assembly; fuel or oil leaks; or loose, missing or damaged parts
7. Fuel in main and day tanks is sufficient and free of excess water and other contaminants
8. Oil and coolant levels are sufficient, fluids are contaminant-free, and jacket water heater is operational
9. Engine-alternator operating instructions are posted near the engine, and are clear and easy to use
10. Adequate ear/eye protection & spill kit available in engine room, and adequate warning labels are posted
11. Ensure that engine, engine room metallic parts & lines, and alternator neutral are all grounded per Pub 77355
12. Engine crankcase breather is vented to atmosphere or discharge damper
13. With engine mfg and installer present perform a first test of the genset with the engine at full load (use load bank) for 2-4 hrs (preferably run test on site; however, test may be at the mfg location with CenturyLink ™ present). Observe all functions, readings, alarms, etc., & note abnormalities, paying attention to following:
A. Water, fuel, and oil temperatures and pressures are within limits
B. Ensure proper operation of the transfer switch
C. Frequency, current, kW, and voltage readings are correct, and within limits
D. Test all alarms during run, both locally and to the Alarm Center for proper operation
E. If provided, rectifier sequencing functions properly
F. Exhaust pressure is less than limits; no exhaust leaks; internal exhaust pipes insulated; 9" minimum exhaust clear from combustibles; hot "reachable" parts guarded/insulated and/or labeled; exhaust couplings use bolted flanges with gaskets or threaded pipe; has a flexible connection to engine and flexible supports to allow for expansion/contraction; and end of exhaust stack protected
G. Ensure proper operation of all fuel pumps, and the day tank (where applicable)
YES NO
H. Intake/exhaust fans/louvers operate (and held open by spring on power loss), and are properly sized per drawings. (Check proper intake size by seeing if engine room door opens easily). Air intake filters are properly installed. (Exhaust fans to be controlled by room thermostat, if separate.) Exhaust is positioned so that its gasses & heat are not part of the intake air.
I. If provided, paralleling functions properly
J. Current load is reasonably balanced between phases
K. All required gauges, meters, and local and remote alarms are present as per Chapters 7, 8 and 13
L. Test the emergency shutdown
14. Check fluids and fuels after run, and visually inspect for leaks, loose parts, etc.
NOTE: Use supplier engine Test and Acceptance too; and when testing alarms and functions, don’t interrupt service
Comments (all No answers must be commented on — Please use the back of this form for comments )
Form 826A Standby Engine Test and Acceptance Checklist
15-15
Chapter 15
Turn Up, Test And Acceptance
CenturyLink
™
TRANSFER SYSTEM AND AC SERVICE ENTRANCE
TEST & ACCEPTANCE CHECKLIST
PUB 77385
Issue K, July 2015
Site:
Engineer:
Date of Installation completion:
Tested by:
Job Number BVAPP:
Job Number Vendor:
Date of Vendor Departure:
Date:
ITEM
1. Ensure proper operation of the transfer system. Simulate an AC failure and return of Commercial AC.
Ensure that all timers function properly. Ensure that transfer instructions are posted (including for portable genset manual transfer switches).
2. If provided, paralleling functions properly and that there are sequencer lights or meters, which properly operate if paralleling, is to be done manually.
3. Ensure that drawings for the transfer system are on site.
4. Ensure that a single line-drawing is on site (it may be physically etched or drawn on the AC switchgear)
5. Visually inspect (or thermally with a thermal gun or camera) all connections in the transfer system and
AC service entrance cabinets for tightness.
6. Ensure that the AC loads of the site do not exceed bus bar and breaker capacities in the AC switchgear.
7. Ensure that electrical safety equipment is available for the site: electrical gloves, goggles, tags/locks for use in lockout/tag out procedures when AC work is being done, & possibly fire-retardant Nomex gear.
8. Ensure that AC service entrance has a lightning arrestor and/or surge suppressor properly installed.
9. Ensure that AC fail is monitored per phase, & that an AC fail alarm properly reports to the Alarm Center
10. If the site is equipped with a power monitor (PSMC), verify that AC voltage (per phase, line-neutral) and currents (per phase) are monitored and reading properly.
11. Ensure that the power company transformer, the engine, the engine breaker, and the main site AC breaker (and any other critical path or large HVAC AC breakers) are at least 125% of the peak summer load (recharging batteries after a building blackout test).
12. Ensure that the AC Service Entrance and Transfer System are grounded per Pub 77355
13. Ensure there is kAIC coordination from the power company transformer down to the PDSCs (e.g., ensure that the kAIC of the service entrance equals or exceeds that of the power company transformer, etc.)
14. Ensure that all AC power panels are properly labeled, including the location of the upstream panel.
Ensure that unused knockouts and open breaker positions in AC panels are covered.
15. Ensure that AC utility phone # and meter # is posted/marked at the main HSP
YES NO
NOTE: Use supplier documentation, for Test and Acceptance
NOTE: When testing alarms and functions, be sure not to interrupt service
Comments (all No answers must be commented on — Please use the back of this form for additional comments)
Form 826B Transfer System and AC Service Entrance Test and Acceptance Checklist
15-16
PUB 77385
Issue K, July 2015
™
CenturyLink
FUEL TANK, FUEL SYSTEM, AND FUEL MONITOR
TEST & ACCEPTANCE CHECKLIST
Chapter 15
Turn Up, Test And Acceptance
Site:
Engineer:
Date of Installation completion:
Tested by:
Job Number BVAPP:
Job Number Vendor:
Date of Vendor Departure:
Date:
ITEM
1. Fuel in main and day tanks is sufficient and free of excess water and other contaminants
2. Ensure that outdoor tanks are placed so that water will not flow into them or pool on top of them.
3. If the outdoor Diesel fuel tank is aboveground in a climate where temperatures may get below 32˚ F, ensure that the tank either is using winter blend Diesel fuel, or is equipped with a tank heater.
4. Visually ensure that all fuel tanks (both main and day) have containment that will contain all of the fuel in the tank in case of a leak. For open containment, ensure it is free of leaks, water, and debris. For sites that have the capacity to store 1320 or more gallons of fuel on site, they are also required to have an SPCC plan.
5. Inspect tank(s) and all fuel piping and pumps for any leaks
6. Ensure fuel lines are connected to engine through a flexible section
7. Fuel Lines installed and routed in accordance with the vendor-supplied Engineering specs and drawings.
8. Verify that an anti-siphon valve is installed on the fuel suction line at the first entrance point to the generator room or enclosure when the main tank is higher than the engine or day tank. (In some jurisdictions, the fuel line is required to have a meltable link valve that closes in case of fire.)
9. Verify that electric fuel solenoid (operating from the engine start and/or control batteries at 12 V or 24 VDC when there is no day tank), or anti-siphon valve as an alternative on sites w/o day tanks, is installed on the supply line (requirement waived when tank lower than engine). Solenoid must be connected to generator run circuit in the control panel. This solenoid should close when the emergency stop button is pushed.
10. Verify that fuel lines running on the floor are routed so as not to create a safety hazard. (Fuel lines lying on the floor should be covered with a metal shroud painted yellow or yellow with black diagonal stripes.)
11. Diesel fuel lines are Aeroquip/Stratoflex hose or black iron. (Aeroquip/Stratoflex lines are permitted, but must be run inside containment conduit). Galvanized pipes/fittings are permitted for LPG and natural gas.
12. Verify that the fuel return line is free from all obstructions. (No gates, valves, or traps are permitted.)
13. Ensure proper operation of all fuel pumps, plus any day tank valves
14. Ensure that a low fuel alarm is reported (may be reported as a generic fuel system trouble) all the way to the Alarm Center. The low fuel alarm should report when there is 8 hours or more of fuel.
15. If the site is equipped with a fuel tank monitor, ensure that it has at least a generic fuel system trouble alarm wired and reporting all the way to the Alarm Center.
YES NO
16. Ensure fuel tank monitor is equipped with a dialup modem and a working phone line (some radio sites and other sites where phone service is inaccessible may be exempt from this requirement), and that the
Power Alarm Center and the local Power Crew have that number.
17. Ensure that the fuel tank monitor is equipped with paper tape and ink, and a method of storing the tape.
18. If the tank is vaulted, and the vault is an OSHA-defined “confined space”, ensure that it is so marked. Also ensure that tanks are marked with the appropriate signage for the fuel type.
19. Ensure that all fuel lines and tanks are properly grounded according to CenturyLink ™ Tech Pub 77355.
NOTE: Use supplier documentation for Test and Acceptance; and when testing alarms and functions, don’t interrupt service
Comments (all No answers must be commented on — Please use the back of this form for comments )
Form 826C Fuel Tank, Fuel System, and Fuel Monitor Test and Acceptance Checklist
15-17
Chapter 15
Turn Up, Test And Acceptance
CenturyLink ™
RT/PREM SITE TEST & ACCEPTANCE CHECKLIST
PUB 77385
Issue K, July 2015
Site:
Engineer:
Date of Installation completion:
Tested by:
Job Number BVAPP:
Job Number Vendor:
Date of Vendor Departure:
Date:
ITEM
1. Ensure that internal and external grounding is per CenturyLink ™ Tech Pub 77355.
2. Do ventilation and exhaust openings have free access
3. Ensure that the site and all of the bays and wiring in the RT are properly tagged/stenciled
4. Ensure proper operation of A/C, sump pump, gas monitor and other environmental systems with the vendor present for CEVs, CECs, and huts, as applicable
5. Ensure safety equipment (e.g., fire extinguisher, first aid kit, gloves, eyewash fluid, etc.) is present, as applicable
6. Ensure that all holes in a CEV are properly sealed
7. Emergency lighting, gas monitors, environmental controllers, or any other device that should be powered by -48 VDC is connected to the DC Plant.
8. Site is properly constructed, landscaped, and backfilled; and weeds are abated
9. Portable genset connection available and sized properly. Verify that a genset can be parked within 30 ft of the transfer system, and that the soil is such that there is access under adverse weather conditions. After turn-up, transfer the site to the engine to confirm backup.
10. Site has records/forms for proactive maintenance of the power plant. Ensure that the power plant was turned up correctly per Forms 822 through 823B. Load test the plant & batteries.
11. Ensure continuity of power and environmental alarms, and any other alarms to the appropriate NOC. (See Chapter 13 for power and environmental alarm standards.)
12. Lightning/surge arrestor installed in power pedestal, and power pedestal wired per NEC ®
13. Confirm that controlled environment sites are set to operate within 55-85° F.
YES NO
This checklist should be performed with the installer(s)/contractor(s) on site. Note below all problems they fix.
Comment below or on back (all No answers must be commented on)
Form 827 RT/Prem Site Test and Acceptance Checklist
15-18
PUB 77385
Issue K, July 2015
CenturyLink ™
BUILDING GROUNDING TEST & ACCEPTANCE CHECKLIST
Chapter 15
Turn Up, Test And Acceptance
Site:
Engineer:
Date of Installation completion:
Tested by:
Job Number BVAPP:
Job Number Vendor:
Date of Vendor Departure:
Date:
ITEM
1. The site ground is the proper size, and installed in accordance with the site record drawings, Engineering instructions, and CenturyLink ™ Technical Publication 77355
2. Both ends of all site ground cables are tagged, and designated to show opposite end terminating location
3. If ground leads are run through metallic conduit both ends of the conduit or sleeve are bonded to the ground lead.
4. Isolated frames, cabinets, rectifiers, etc. containing AC service are properly grounded per Tech Pub 77355 Chapters 8 and 9
5. If associated switching system uses isolated grounding, integrity must meet the system requirements spelled out in CenturyLink ™ Technical Publication 77355
YES NO
Test & Acceptance should be performed with the installer on site. Note below all problems they fix
For a complete grounding review, contact the CenturyLink ™ Power Maintenance Engineer
Comments (all No answers must be commented on)
Form 828A Building Grounding Test and Acceptance Checklist
15-19
Chapter 15
Turn Up, Test And Acceptance
CenturyLink ™
POWER DISTRIBUTION BUS BAR & CABLING
TEST & ACCEPTANCE CHECKLIST
PUB 77385
Issue K, July 2015
Site:
Associated Power Plant:
Engineer:
Date of Installation completion:
Tested by:
Job Number BVAPP:
Location:
Job Number Vendor:
Date of Vendor Departure:
Date:
ITEM YES NO
1. AC bus duct and conduit is installed in accordance with site record drawing layout, the manufacturers' specifications, and the NEC ®
2. The proper type and size fuses and/or circuit breakers are installed in AC bus duct plug-in units
3. Warning labels are placed at all access openings and end sections of AC bus duct, as required
4. Bus bar is installed in accordance with site record drawing layout
5. Bus bars and risers are stenciled to properly identify CHARGE, DISCHARGE, BAT,
GRD, RTN, voltage, etc.
6. The ammeter shunt is properly mounted and stamped to indicate voltage and
Ampere rating
7. Installation meets CenturyLink ™ workmanship standards, and is in accordance with Engineering standards and drawings, as spelled out in CenturyLink ™
Technical Publications 77350, 77351, 77352, 77355 and this one
8. Bus bars, joints, and terminating connections to bus bars are free of excessive heat.
(Technicians may use contact thermometers, or infrared temperature guns to determine heating. If major problems are suspected, a CenturyLink ™ Power
Maintenance Engineer or outside thermographer may be called in to do a thermal camera scan.)
9. Power cable is routed in accordance with site record drawings
10. Power cable is run and secured on cable racks
11. Adequate insulating protection is provided on cable rack straps, stringers, thread rods, auxiliary frame bars, and other metallic objects where power cable makes contact with sharp surfaces, or at tie points on soft rubber outer jackets.
12. Power cable insulation is free of damage
13. Terminating wires and cables are properly tagged and designated at both ends of conductors when required, and unused power cables have an insulating cap.
14. All cables listed on power cable running list are installed with correct type and size of cable as specified, or otherwise calculated
Test & Acceptance should be performed with the installer on site. Note below all problems they fix.
Comments (all No answers must be commented on)
Form 828B Power Distribution Bus Bar and Cabling Test and Acceptance Checklist
15-20
PUB 77385
Issue K, July 2015
Chapter 15
Turn Up, Test And Acceptance
CenturyLink ™
POWER AREA FLOOR PLAN TEST & ACCEPTANCE CHECKLIST
Site:
Associated Power Plant:
Engineer:
Date of Installation completion:
Tested by:
Job Number BVAPP:
Location:
Job Number Vendor:
Date of Vendor Departure:
Date:
ITEM
1. Power equipment is located and designated as shown on floor plan drawing
2. All cable holes appear to be closed properly (wall, ceiling, and floor type, as applicable)
3. Wall and column mounted equipment are properly located and shown on floor plan, cable rack plan, or other associated site record drawings
4. Power Equipment has adequate clear working space per the NEC ® and Tech Pub
77351.
YES NO
Test & Acceptance shall be performed with the installer on site. Note below all problems they fix.
Comments (all No answers must be commented on)
Form 829A Power Area Floor Plan Test and Acceptance Checklist
15-21
Chapter 15
Turn Up, Test And Acceptance
PUB 77385
Issue K, July 2015
CenturyLink ™
POWER DOCUMENTATION TEST & ACCEPTANCE CHECKLIST
Site:
Associated Power Plant:
Engineer:
Date of Installation completion:
Tested by:
Job Number BVAPP:
Location:
Job Number Vendor:
Date of Vendor Departure:
Date:
ITEM
1. All new power equipment drawings furnished on this project are in acceptable condition
2. All power drawings that were supposed to be provided with this job were provided
3. All operating and maintenance instructions for new or added power equipment are available and accessible at the site
4. All installer job completion reports are available
5. Installer(s) followed written MOPs
6. Are all necessary SDS (formerly MSDS) sheets available on site
YES NO
Test & Acceptance should be performed with the installer on site. Note below all problems they fix.
Comments (all No answers must be commented on)
Form 829B Power Documentation Test and Acceptance Checklist
15-22
PUB 77385
Issue K, July 2015
CenturyLink ™
LARGER SITE POWER EQUIPMENT INVENTORY
Chapter 15
Turn Up, Test And Acceptance
OFFICE:
ADDRESS:
Voltage & Polarity:
Plant/Controller Mfg/Mdl
Plant Size (shunt/bus Amps)
Rectifier Qty & Models:
Battery Strings & A-hr Size:
Battery Mfgs & Models:
Battery Installation Dates:
Plant Load in Amps:
PDSC Bus/Feed Brkr Size:
Add Rect. max AC loads
CLLI:
TECH:
BATTERY PLANTS
Plant #1 Plant #2
DATE:
PHONE:
Plant #3
Voltage & Polarity:
Mfg & Model:
Associated Battery Plant:
Qty & Sizes of Converters:
Plant Load in Amps:
Mfg/Model:
Ringers:
Tone Generators:
Mfg & Model:
RING PLANT(S)
RR:
Interrupters:
Installation Date:
INVERTER(S)/UPS
CONVERTER PLANTS
Plant #1 Plant #2 Plant #3
PSMC MONITOR and OTHER ALARM DEVICES
PSMC Mfg & Model:
Software Version:
Dial-Up #:
X.25/IP Ckt #:
Other Alarm Devices (e.g., Dantel, etc.):
Size, AC Voltage/Phase:
Load (AC Amp/kVA):
Associated Battery Plant:
Installation Date:
Voltage & Phase:
Size (Amps):
COMMERCIAL AC
Lightning Arrest Frame & Model:
ENGINE & TANK DATA
Engine Mfg& Model:
Voltage & kW:
Install Date (note if not Autostart):
Fuel Type & Consumption (gal/hr):
Actual Engine Load (in kW):
Start Batt Mfg& Model:
Start Batt Install Date:
PORTABLE GENSET INFORMATION
Plug Frame, Mod, & Size (Amps):
Portable Frame, Size, Fuel:
Storage Location:
Transfer System Type/Size:
Day Tank Capacity (gal):
Main Tank Type & Capacity (gal):
Tank Monitor Mfg & Model:
NOTES & COMMENTS (use back of sheet as needed) Tank Monitor Dialup:
Retain a copy of this form and send a copy to the CenturyLink ™ Power Engineers
Form 840 Larger Site Power Equipment Inventory
15-23
Chapter 15
Turn Up, Test And Acceptance
PUB 77385
Issue K, July 2015
CenturyLink ™
BDFB OR POWER BOARD PANEL FUSE/BREAKER ASSIGNMENT RECORD
Site:
Address:
Tech:
PBD/RR of this BDFB/PBD:
CLLI:
Feeder Fuse/Breaker PBD & Position:
Date:
Phone/Pager:
PANEL(s):
Feeder Fuse/Breaker Size: Panel Load:
Position Equipment & Relay Rack Fed
Fuse or
Brkr Size
Mfg L-2
Drain
Totals
Additional panels may be placed on additional sheets.
List 2 drains are peak drains
List 1 drains are average drains
Assigning fuses from the bottom to the top of a bay or panel (or inside to outside for horizontal panels) eases future installation and reduces cable congestion as needed
Contact your Design Engineer for a fuse assignment (if those are tracked in your area)
Please note if this Panel is "bused" or "cabled" in the rear to adjacent panels (e.g., C, A2, etc.)
Information for all columns may not be available to you — some columns are for Engineering use, and some for the "field"
Notes:
Mfg L-1
Drain
Actual
Load
Form 841 BDFB/PBD Panel Fuse/Breaker Assignment Record
15-24
PUB 77385
Issue K, July 2015
CenturyLink ™
CRITICAL LARGER SITE POWER ALARM VERIFICATION
Chapter 15
Turn Up, Test And Acceptance
Alarm Alarm system ticket #
Notes
Commercial AC Fail
Power Major
Power Distribution Fuse/Breaker Major
Critical Power Alarms
Low Voltage and/or Battery on Discharge
Very Low Voltage (if applicable)
High Voltage
Rectifier Fail Major
Ring Plant Major
Low Voltage Disconnect (where applicable)
Engine Run
Engine Fail/Major
Low Fuel / Fuel System Trouble
Alarm Center Contact Person:
Site CLLI:
Alarm Center Phone:
Site Address:
Alarm Telemetry System Type:
X.25 or IP (PSMC) e-tel (Dantel, E2A, etc.)
Installer performing the test and company
NROC Tech with whom Test performed:
Phone:
Phone:
Switch or other
It may not be wise to test some alarms except in the Maintenance Window due to the possibility to cause an outage if they are truly tested; and/or in some cases, it may be best to simply verify alarm continuity by shorting the alarm pins instead of actually bringing in the alarm, for the same reasons
Additional Notes:
Form 844 Critical Larger Site Power Alarm Verification
15-25
Chapter 15
Turn Up, Test And Acceptance
CenturyLink ™
SMALLER SITE POWER EQUIPMENT INVENTORY
PUB 77385
Issue K, July 2015
Common Name of Location
State
CLLI
Address
Upstream Office (serving Wire Center)
Access & Directions
Map or GPS coordinates
Customer (primarily for Customer Prem sites)
Site Type (RT, CEV, UE, CEC, hut, rptr, CPE)
(List RTs by type: e.g., 80 cabinet, etc.)
Date of this review
Reviewer name & contact #
Air-conditioning type & maintenance contact
Power plant type (also list J-spec, KS-, or mdl )
Load (in Amps)
# Rectifiers
Rectifier type [also list the model number(s)]
Rectifier size(s)
Float voltage
# Battery strings
Battery type (model #, KS-spec, etc.)
Battery size (A-hrs)
# cells/monoblocs per string
Battery installation date(s)
Residual Ring plant type (model number, etc.)
Comm. AC voltage, phase, and Amp rating
Generator Plug Mfg., type, and size
Alarm system (E-tel, X.25, overhead, etc.)
Alarm Center & Center phone #
CIRCLE ALARMS THAT ARE PRESENT (Add any others not listed here)
POWER MJ POWER MN RECT. FAIL AC PWR FAIL
Notes:
Form 845 Smaller Site Power Equipment Inventory
15-26
PUB 77385
Issue K, July 2015
CenturyLink ™
SMALLER SITE HOUSEKEEPING ALARM VERIFICATION
Chapter 15
Turn Up, Test And Acceptance
N/A Alarm Works? Doesn’t
Work?
Commercial AC Fail
Power Major
Power Minor
High Battery Temperature
Power Distribution Fuse/Breaker
Low Voltage and/or Battery on Discharge
Very Low Voltage
High Voltage
Rectifier Fail (list the number of these alarms if more than 1)
Ring Plant Major
Ring Plant Minor
High Temperature (of the enclosure)
Explosive Gas Alarm
Toxic/Explosive Gas Alarm (combined)
Ventilation/Fan Fail
Air-Conditioner Failure
Tech Performing Test:
Site CLLI: Site Address:
Phone/Pager:
X.25 overhead (fiber mux)
Alarm Telemetry System Type: e-tel
NROC Tech with whom Test performed:
(Dantel, E2A, Westronics)
Additional Notes:
Phone: other (list)
Form 846 Smaller Site Housekeeping Alarm Verification
15-27
PUB 77385
Issue K, July 2015
Chapter 16
Definitions and Acronyms
CONTENTS
Chapter and Section Page
16. Definitions and Acronyms ....................................................................................... 16-1
TOC 16-i
PUB 77385
Issue K, July 2015
16. Definitions and Acronyms
Chapter 16
Definitions and Acronyms
5E
A or Amp
A2LA
A/B
ABC
ABS
AC
5ESS
™
Amperes (amount of current flow)
American Association for Laboratory Accreditation redundant (dual) feeds; typically referring to DC systems
Area Bus Centers
A/C
ACEG ach
ACO
ACT
ADSL
AGM
Alarm Battery Supply (small fusing at the power plant for the controller)
1) Alternating Current
2) Armor-Clad (certain cable types with a metallic wind outer jacket)
Air-Conditioning
Alternating Current Equipment Ground air changes per hour
Alarm Cut-Off
Ah or A-hr
AHJ
A.I.C.
Activate
Assymetric Digital Subscriber Line
Absorbed Glass Matte (VRLA battery separator-absorbed electrolyte)
Ampere-hour (rating of a battery to deliver so many Amps for so many hrs)
Authority Having Jurisdiction (Fire Marshal, Electrical Inspector, etc.)
Amps of Interrupting Current (capability to withstand)
AID aka
Access IDentifier (identifies a specific piece of equipment) also known as alm or al or ALRMS Alarm(s)
Alt
ALW
ANTS
ANSI
API
ASCII
ASHRAE
ASME
Alternator
Allow
Abnormal Network Tracking System (CenturyLink
™
outage reporting method)
American National Standards Institute
American Petroleum Institute
American Standard Characters for Information Interchange
American Society of Heating, Refrigerating, and Air-conditioning Engineers
American Society of Mechanical Engineers
16-1
Chapter 16
Definitions and Acronyms
AST
ASTM
PUB 77385
Issue K, July 2015
Above-ground Storage Tank (includes vaulted tanks below ground)
American Society of Testing Materials
ATIS
ATS
Alliance for Telecommunications Industry Solutions
1) Automatic Transfer Switch/System
2) Acceptance Testing Specification
ATTR
AUD
Attribute
Audible (nominal 86 VAC 20 Hz superimposed ringing)
AUX avg
Auxiliary average
American Wire Gauge AWG
AXE
™
BAT or Batt or B
Automatic Cross-connection Equipment
Battery
Bay Command Console (a type of DMS
™
switch bay) BCC
BDB Battery Distribution Board — see PBD
BDFB or BDCBB Battery Distribution Fuse (or Circuit Breaker) Board/Bay
BET Building Entrance Terminal
B(r)kr or BR(K)
BMS
BOD
BP bps
BPSC
BS
BTBA
BVAPP
BX c
C cab
CAD
Breaker
Battery Management System
Battery on Discharge
Bypass bits per second
Building alarm Point, Scan and Control
British Standard
Battery Termination Bus Assembly (chandelier, or main term bars)
Billing Verification Authority Purchasing Project (CenturyLink
™
job #)
An older type of AC (armor-clad) cable cells
1) degrees Celsius
2) battery Capacity
3) Common (grounded) alarm contact cabinet
Computer-Aided Drawing
16-2
ccs
CDC
CdO
CEC
™
CEM
CEMF
CEV
CFA
CFR
PUB 77385
Issue K, July 2015
CANC cap
CATV
CB
CCA char
Chg
Ckt or CRCT
CL
CLAS
CLEC
CLLI
™
Cntrl
CO coax
COE-FM
COGB
COM(M) or com combo
Chapter 16
Definitions and Acronyms
Cancel capacitor traditional cable TV hybrid fiber-coax network
Circuit Breaker
Cold Cranking Amps centi-call seconds (or hundreds of call seconds — full usage is 36 ccs/hr)
Centers for Disease Control and Prevention
A small Central Office (Community Dial Office)
Controlled Environmental Cabinet (half-buried walk-in hut/vault)
Construction Engineering Memorandum
Counter-Electro Motive Force cell
Controlled Environmental Vault
Converter Fail Alarm
1) Controlled Ferro-Resonant rectifier
2) Code of Federal Regulations character
1) Charge(r) – sometimes known as a rectifier
2) change circuit
Confined Location
Classification
Collocated Local Exchange Carrier
Common Language Location Identifier
Control
Central Office coaxial waveguide cable
Central Office Equipment – Facilities Management (CAD system)
Central Office Ground Bus
1) Communications
2) commercial combination card (both POTS and DSL on the same card)
16-3
Chapter 16
Definitions and Acronyms
COML or COMM Commercial (AC) comp Compensation (as in temperature compensation)
COND config
CONT
Condition
(standard) configuration
Control
CONV/cnvrter/C Converter
COOL/CO/ C/CLT Coolant
COT
CP
Central Office Terminal
Chlorosulfonated Polyethylene (type of cable insulation)
Crit or CR or CAT Critical alarm
CRNK or CRK
CSPEC
CT
Crank
Common Systems Planning and Engineering Center
Current Transformer
PUB 77385
Issue K, July 2015
CURNT or CUR d
D daisy chaining dB dBa dBrnC
DC or D.C. delta or
Δ demarc
DIESL or DSL diff
Disc or DISCO
Current (in Amperes) distance
Distribution running multiple bays/shelves off of a single fuse/breaker position deciBels deciBels audible deciBels referenced to noise weighting C (POTS voiceband)
Direct Current method of providing 3-phase power demarcation point between phone company and premises wiring
Diesel differential
Disconnect
Digital Subscriber Carrier System
DISC
*
S
Dist or DIS
DLC
DLO
DLT
Distribution
Digital Loop Carrier
Diesel Locomotive (wire — Class K wire stranding)
Delete
16-4
PUB 77385
Issue K, July 2015
DMM
DMS
™
Chapter 16
Definitions and Acronyms
Digital MultiMeter
Digital Multiplexing System (family of Nortel Class 5 switches) the smaller power wire, tapped to the main conductor, to enter a bay drop
DSCH(R)G/DIS(CH) Discharge
DS-0 Digital Signal (level) 0, a digital data rate of 64 kbp/s
DS-1
DS-3
DSL
DSU
DT
Digital Signal 1, a digital data rate of 1.544 Mbps (can carry 24 DS-0s)
Digital Signal 3, a digital data rate of 50 Mbps (can carry 28 DS-1s)
Digital Subscriber Line (high speed copper carrying data or video)
Data Serving Unit (modem for packet circuits, like X.25)
DTMF
E2A
Day Tank
Dual Tone Multi-Frequency
E-telemetry 2 nd
generation Alarm surveillance protocol (polled from the master alarm system via a relatively slow 4-wire data circuit)
EAT
ED
EDLC
Engine Alarm Termination box
Edit
Electric Double-Layer Capacitor (Super™ or Ultra™ Capacitor)
EEE Electronic Equipment Enclosure
EMER or Em(er)g Emergency
EMC Electro-Magnetic Compatibility
EMI
EMT
EN
Eng or E env or enviro(n)
EoCu
EPA
EPO
EPR/EPDM
E/Q eqpt
ESD
Electro-Magnetic Interference
Electrical Metallic Tubing
English (notation for IEC standards to note the language it is written in)
Engine environment(al) ethernet over copper
Environmental Protection Administration
Emergency Power Off switch/button
Ethylene Propylene Rubber (a type of wire insulation material)
Earthquake equipment
Electro-Static Discharge
16-5
Chapter 16
Definitions and Acronyms
ESS
™
Electronic Switching System e-tel
PUB 77385
Issue K, July 2015 e-telemetry (an alarm protocol for edge devices using E2A or IP transport)
ETP
EXT
F
FA
FB
FCC
Electrolytic Tough Pitch (hard-drawn copper)
External
1) degrees Fahrenheit
2) Farad (unit of capacitance)
3) Float (as in voltage or charge)
Fuse Alarm
Fuse Bay
Federal Communications Commission
Fail FL or F
FR
FRP
FS
Family of Requirements
Fiber-Reinforced Polymer fuse
FSP ft
FTTB
FTTC
FTTH
FTTP
Fuse Supply Panel feet
Fiber to the Business
Fiber to the Curb
Fiber to the Home
Fiber to the Premise
FX
G gal
GEN or G genset
GF(C)I
GN
GND or GRD
GPDF
GPS
Foreign Exchange rectifier Group (number) gallon
Generator standby engine-alternator (typically the portable type)
Ground Fault (Circuit) Interrupter
General
Ground
Global Power Distribution Frame for a Lucent 5ESS
™
switch
Galaxy
™
Power System (from Lineage Power)
16-6
PUB 77385
Issue K, July 2015
Chapter 16
Definitions and Acronyms
GR Generic Requirements
Hardened Equipment Equipment that must operate at the temperature extremes of -40 to +65° C
HDR
HDSL
HI or H hka hp
Header
High bit-Rate Digital Subscriber Line
High housekeeping (environmental or power) alarm horsepower
HM hr or h hrsm
HSP html
HVA
HVAC
HVSD
Hz
I
Host Message hour host-remote switch module
House Service Panel
Hyper-Text Markup Language
High Voltage Alarm
Heating, Ventilation and Air-Conditioning
High Voltage Shut Down
Hertz (frequency — cycles per second)
1) current (in Amperes)
2) Inverter
International Annealed Copper Standard IACS
ICA
ICC
ICEP
ICS
ID or IDNT
IEC
InterConnection Agreement
International Code Council
Inductive Coordination and Electrical Protection
Industrial Controls and Systems
IDentifier
International Electro-Technical Commission
IEEE
INH
INIT inter inv or INVERT
INV
Institute of Electrical and Electronic Engineers
Inhibit
Initialize interruptor (part of some residual ring plants) inverter
Inventory
16-7
J k
K
Chapter 16
Definitions and Acronyms
IOF
IP
Inter Office Facilities
Internet Protocol
IR
ISDN
IT
ITU-T
IXC infrared
Integrated Services Digital Network
Information Technology (computer room)
PUB 77385
Issue K, July 2015
International Telecommunications Union (Telecom standardization sector)
IntereXchange Carrier
Joules kilo (1000) kcmil
KS
L constant representing the resistance of copper or aluminum kilo circular mils (a circular mil is the area of a circle with a dia. of
1
/
1000
”)
Kearney Specification (a manufacturing standard from Western Electric)
Low
L-
LATA
LED
LEL
Li
LIGTN or LTNG
LMP
LNS
LO or LW or L
LOI
LPDU
LPG
LS
LSSGR
LVA
LVBD
LVD
LVLD
List number (part of the end of some telecommunications part numbers)
Local Access Transport Area (separates local from long distance carrier call)
Light Emitting Diode
Lower Explosive Limit
Lithium
Lightning
Lithium Metal Polymer (battery)
Local Network Services (a CenturyLink
™
internal division)
Low
Limiting Oxygen Index
Load Power Distributing Unit for a 5ESS
™
Liquid Propane Gas
Low Voltage Battery Disconnect
Low Voltage Disconnect
Low Voltage Load Disconnect
switch
Low-Voltage Surge
LATA Switching System Generic Requirements
Low Voltage Alarm
16-8
MG
MGB
MGN
MI
MIB
μ mil min
Maj or MJ max
MC
MCM
MCS
™
MDed
Mdl
MEAS
Megger
™
Mfg
PUB 77385
Issue K, July 2015 m
M
Min or MN misc mod
MOP
MOV
MP
MSG
Chapter 16
Definitions and Acronyms
1) milli (thousandth)
2) meter
1) mega (million)
2) Module/Main
3) Micro (as in microprocessor)
4) midpoint
Major alarm maximum
Metal-Clad cable (a specialized type of armored cable that is sealed to gas) thousand circular mils (old designation — modern one is kcmil)
Microprocessor Controlled System (Trademark of Lineage Power)
Manufacturer-Discontinued
Model (number)
Measure megohmmeter
Manufacturer
Main Generation or Motor Generator
Main Ground Bus (in the Ground Window) the power company’s Multi-Grounded Neutral
Mineral Insulated cable (copper and magnesium-oxide outer jacket)
Management Information Base (vendor-provided SNMP manager template) micro (millionth, or precursor to processor) thickness or diameter of one-thousandth of an inch
1) minute
2) minimum
Minor alarm miscellaneous module
Method of Procedure (used to define installation steps)
Metal-Oxide Varistor
Micro-Processor
Message
16-9
N
N81
N/A
NA
NACE
®
N.C. or NC
NE
NEBS
™
NEC
®
NEMA
®
NETA
™
NESC
®
NFPA
®
Chapter 16
Definitions and Acronyms
MTB mux
Main Term Bar(s) multiplexer
MVPC or mvpc
η
N or n minimum Volts per Cell efficiency number
PUB 77385
Issue K, July 2015
Negative
No parity, 8 bits, 1 stop bit (modem communications protocol setting)
Not Applicable
Not Available
National Association of Corrosion Engineers
Normally Closed contacts (open on alarm) intelligent Network Element
Network Equipment – Building System
National Electrical Code
National Electrical Manufacturer's Association
National Electrical Testing Association
Ni-Cad or NiCd
NID
NIL
NIOSH
NMA
®
NMH or NiMH
National Electrical Safety Code
National Fire Protection Association
Nickel Cadmium
Network Interface Device (demarc between company and premises wiring) none
National Institute for Occupational Safety and Health
NNS or NSD
N.O. or NO
NOC
NORM
NR
NROC
NRTL
Network Monitoring and Analysis
Nickel-Metal Hydride
National (Network) Services (Division) - long-haul CenturyLink
™
division
Normally Open contacts (close on alarm)
Network Operations Center (generic term for alarm center)
Normal
No Redundancy
Network Reliability and Operations Center (CenturyLink
™
Alarm Center)
Nationally Recognized Testing Laboratory
16-10
ocs
OCV
OF
OMNPLSE
ONU
OPAC
™
OPGP(B)
OPM
™
OPR
ORM
™
OSHA
OSMINE
™
PUB 77385
Issue K, July 2015
NTA
NSA
NUM or N or n
NVLAP
Ω
O
OAU
OSP
OSS
OVER or O ovly p
P
PAD
PBD
Chapter 16
Definitions and Acronyms
National Telecommunication Association
Non-Service Affecting
Number
National Voluntary Laboratory Accreditation Program
Omega (the greek letter representing Ohms, the unit of electrical impedance)
On
Office Alarm Unit
Operation Communications System
Open-Circuit Voltage
Output Fail
Omnipulse
™
(an older AT&T/Lucent power monitor)
Optical Network Unit
Outside Plant Access Cabinet
Office Principal Ground Point (Bus)
Outside Plant Module
Operate
Optical Remote (switching) Module
Occupational Safety and Health Administration
Operations Systems Modifications for the Integration of Network Elements
(Ericsson Telcordia
®
process for ensuring equipment and equipment peripheral system compatibility with Telcordia’s OSS systems)
Outside Plant
Operational Support Systems
1) Overcrank
2) Overspeed overlay pairs
1) Positive
2) Power
Packet Assembler/Disassembler
Main DC Power Distribution Fuse/Breaker Board
16-11
Chapter 16
Definitions and Acronyms
PC
PDC/F
Pilot Cell
PUB 77385
Issue K, July 2015
Power Distribution Cabinet/Frame (switch secondary distribution point)
PDSC
PDU
Power Distribution Service Cabinet (AC cabinet feeding the rectifiers)
AC Power Distribution Unit (data center floor mount cabinet or rack shelves/strips)
Professional Engineer P.E.
PEI
™
PES pf (power factor)
PFC
Petroleum Equipment Institute
Power and Environment System (a type of DMS
™
remote switch message) the cosine of the phase angle between AC Voltage and current peaks
PF(D)
PG ph or Ø or PHSE
Power Factor Correction
Power Fuse (Distribution) Bay for a switch
Pair Gain
Phase (of AC)
PLC plt
PM
Programmable Logic Controller plant
1) Power Message
2) Power Monitor
Power over Ethernet PoE
POTS
Prem
PRES or PRESS
PRI
PROC
PSAP
PSMC pt
PT
PTC
Pub
PV
PVC
Plain Old Telephone Service commercial Customer Premises
Pressure
Primary (power plant or distribution)
Processor
Public Safety Answering Point
Power System Monitor Controller point
Potential (voltage) Transformer
Positive Temperature Coefficient (variable resistor)
Publication
Photo-Voltaic
Poly-Vinyl Chloride (plastic)
16-12
Rm rms
RNG
RO
ROH
RoHS
ROW rpm
RPM
Ratel
RCS
RCU
Rect or REC redf
Reg
Regen
REPT
REV
RFA
RG
RHH
RHW
RLCM
™
RLS
PUB 77385
Issue K, July 2015
Pwr or POWR
Q&A
R
Chapter 16
Definitions and Acronyms
Power
Question and Answer (CenturyLink
™
Engineering tool)
1) Resistance
2) Run
3) Ring(ing)
4) Remote
5) Rated capacity
Ratelco (a former manufacturer of rectifiers, power monitors, etc.)
Remote Concentrator – Subscriber
Remote Carrier – Urban
Rectifier redefine
Regulation regeneration
Report
Reverse
Rectifier Fail Alarm
Regional (part of a standard practice or form # for CenturyLink
™
LNS)
Rubber, extra-High temperature (wire insulation)
Rubber, High temperature, Water resistant (wire insulation)
Remote Line Concentrator Module
Release room
Root Mean Square ("effective", "average" AC voltage and current)
Ringing (plant)
Record Only
Receiver Off Hook
Reduction of Hazardous Substances
Right-of-Way
Revolutions per minute
Remote Peripheral Monitor
16-13
s s or sec
SA
SAD
SBR
SCC
(M)SDS
SECU
SELV
SEVER s.g.
SHARP
™
SHNS
™
SHUT
SI
SID
SLC
®
Chapter 16
Definitions and Acronyms rptr
RR repeater
Relay Rack
RS 1) Reverse Service
2) Re-Start
3) Recommended Standard
RSC
™
RT
Remote Switching Center
Remote Terminal
RTN or Rtn
RTRV
RTU
RU
RUS s96
PUB 77385
Issue K, July 2015
Return (bus)
Retrieve
Right-to-use
Rack Unit
Rural Utilities Service
SLC
®
96 (DLC system where 4 T-1s backhaul 96 DS-0 POTS lines) string second(s)
Service Affecting
Silicon Avalanche Diode
Styrene Butadiene Rubber (cable insulation)
Switching Control Center
(Material) Safety Data Sheet
Secure
Safety Extra Low Voltage
Severity
Specific Gravity
Self Healing Alternate Route Protection (CenturyLink
™
-sold architechture)
Self Healing Network Services (architecture sold by CenturyLink
™
)
Shutdown
Système International (d’unités) – the metric system
System ID
Subscriber Loop Carrier
16-14
PUB 77385
Issue K, July 2015
SM
SMR
SNMP
SONET
SPCC
SPCS
SPD
Switch Module
Switch-Mode Rectifier
Simple Network Management Protocol
Synchronous Optical Network
Spill Prevention, Containment, and Control
Stored Program Control Switching System
1) Surge Protective Device
2) Speed specification(s)
Chapter 16
Definitions and Acronyms spec(s)
SR
SRCE
Stby or SBY
STI
®
SUM
SW sync
Special Report
Source
Standby
Steel Tank Institute
Summary
Switch synchronize
Sys or S
T
System
1) Terminate or stop
2) Transfer
3) Temperature
T-carrier rate 1 — physical standard for carrying a DS-1 signal T1 (or T-1)
TA
Tech or tech
Technical Advisory
1) Technical
2) technician telecommunications telecom
Temp or TMP or T Temperature term termination or terminal (bar)
TFFN Thermo-plastic, Flexible, Fixture wire, with Nylon jacket
TH
THD
THHN
3D Condo
Threshold
Total Harmonic Distortion (in the AC source or fed back to it)
Thermoplastic, extra-High temperature, Nylon-jacketed (wire insulation)
A co-location building that is jointly owned.
16-15
TRAN or TRN
Trbl or TBL
TSGR
TTY
TVSS
UBC
™
UE
™
UFC
™
UL
®
UNS-C
UP
UPS
USB
USE
UST
Chapter 16
Definitions and Acronyms
THWN
TIA
®
PUB 77385
Issue K, July 2015
Thermoplastic, High temperature, Water resistant, Nylon-jacketed insulation
Telecommunications Industry Association
TID
TIF
TL1
TLE
TLPU
Target IDentifier (the network element to which a TL1 message is sent)
Telephone Influence Factor
Transaction Language 1 (NE to NMA
®
communication, Telcordia-defined)
Telecommunications Load Equipment
Telecommunications Line Protector Unit
TLS
TNV top to top
TP
TPE
TR
Tape Library System
Telecom Network Voltage from the top of one equipment bay to another, not including drops
Test Point
Thermo-Plastic Elastomer (wire insulation)
1) Technical Reference
2) Terminate Rectifier (shutdown signal)
3) Transfer
4) Trouble
Transfer
Trouble
Transport System Generic Requirements teletype
Transient Voltage Surge Suppression (see also SPD)
Uniform Building Code
Universal Enclosure (half-buried walk-in hut/vault)
Uniform Fire Code
Underwriter's Laboratory
Unified Numbering System for metal (C=Copper) alloys
Upper
Uninterruptible Power Supply
Universal Serial Bus
Underground Service Entrance (cable)
Underground Storage Tank (direct-buried)
16-16
PUB 77385
Issue K, July 2015
V or VLT
VA
Volts
Volt-Amps
Very-high-bit-rate Digital Subscriber Line
Chapter 16
Definitions and Acronyms
VDSL
VFD Variable Frequency Drive (rectified variable speed motor for HVAC)
VG/VLTG/VOLT Voltage
VLV
VOM
VRLA
VT100 w/
W
Very Low Voltage
Volt-Ohmmeter
Valve Regulated Lead Acid
Virtual Terminal Emulation with 100 defined keys
(Class) W
WD
WECO
WFCA
WTR wye or Y
Xfr or XFER
XHHW
XLP with
1) Watt (equal to Volt-Amps for DC, but reduced by power factor for AC)
2) Watch
Welding wire stranding (actually correctly known as Class K)
Wiring Devices
Western Electric Company (manufacturing arm of the former Bell System)
Western Fire Chiefs Association
Water three-phase power, where the center tap is grounded neutral
Transfer
Cross-linked, thermoset, extra-High temperature, Water resistant insulation
Cross-Linked Polyethylene (wire insulation)
16-17
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Chapter 17
Bibliography
CONTENTS
Chapter and Section Page
17. Bibliography ............................................................................................................. 17-1
17.1 Telcordia ® and Bell Labs Publications ...................................................... 17-1
17.2 CenturyLink ™ Technical Publications ...................................................... 17-3
17.3 Miscellaneous Publications ........................................................................ 17-3
17.4 Ordering Information ................................................................................ 17-13
TOC 17-i
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Issue K, July 2015
17. Bibliography
Chapter 17
Bibliography
The following references are bibliographical for referential purposes only, and not binding. All binding requirements are specifically contained in this document. All referenced documents are the latest available issue.
17.1 Telcordia ® and Bell Labs Publications
BR-790-100-656 DC Distribution
GR-26
GR-27
GR-63
GR-78
GR-151
Controlled Environmental Vaults (CEVs)
Environmental Control Systems for Electronic Equipment
Enclosures
NEBS ™ Requirements: Physical Protection
General Physical Design Requirements for Communications
Products and Equipment
24-, 48-, 130-, and 140-Volt Central Office Power Plant Rectifiers
GR-209
GR-221
Product Change Notices (PCNs)
Interface and Functional Requirements for Microprocessor Control of 24-, 48-, 130-, and 140-Volt Central Office Power Plants
GR-230
GR-232
GR-295
GR-347
GR-513
GR-811
GR-833
GR-947
Engineering Complaints
Lead-Acid Storage Batteries
Mesh and Isolated Bonding Networks: Definition and Application to Telephone Central Offices
Generic Requirements for Central Office Power Wire
Power Requirements in Telecommunications Plant
TL1 Messages Index
TL1 Surveillance and Maintenance Messages
GR-974
GR-1089
GR-1275
Generic Requirements for a -48 Volts Telecommunications
Switchmode Rectifier/Power Supply
Telecommunications Line Protector Units (TLPUs)
Electromagnetic Compatibility and Electrical Safety for Network
Telecommunications Equipment
Central Office / Network Environment Equipment
Installation/Removal
17-1
Chapter 17
Bibliography
GR-1500
GR-1502
GR-1515
GR-2832
GR-2834
GR-3020
GR-3108
GR-3150
GR-3168
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Powering Telecommunications Load Equipment (TLE) in
Telecommunications Systems
Central Office / Network Environment Detail Engineering
Detection and Control of Thermal Runaway in VRLA Batteries
Walk-in Cabinets
Basic Electrical, Mechanical, and Environmental Criteria for
Outside Plant Equipment
Nickel Cadmium Batteries in the Outside Plant
Network Equipment in the Outside Plant (OSP)
Secondary Non-Aqueous Lithium Batteries
Nickel Metal Hydride Battery Systems for Use in
Telecommunications
GR-4228 VRLA Battery String Certification Levels Based on Requirements for Safety and Performance
TA-NWT-000370 Generic Requirements for Mechanized Power Room Operations
Monitor (MPROM)
TA-NWT-000406 DC Bulk Power System for Confined Locations
TA-NWT-001360 Generic Requirements for Power Systems Messages at the OS/NE
Interface
TR-NWT-000154 24-, 48-, 130-, and 140-Volt Central Office Power Plant Control and
Distribution Equipment
TR-NWT-001011 Surge Protective Devices (SPDs) on AC Power Circuits
TR-NWT-001223 DC Power Board Fuses
TR-NWT-001293 Permanent Engine-Generators for Remote Electronic Sites
TR-TSY-000757 Uninterruptible Power Systems (UPS)
TR-TSY-000967 Low-Power Telecommunications Power Supply Rectifier
SR-3580
SR-5263
Network Equipment-Building System (NEBS ™ ) Criteria Levels
Code Requirements and Fire Protection Issues for Stationary
Storage Battery Systems in Telecommunications Equipment, Video
Headend and IT Buildings
17-2
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17.2 CenturyLink ™ Technical Publications
PUB 77350
Chapter 17
Bibliography
Central Office Telecommunications Equipment Engineering
Installation and Removal Guidelines
PUB 77351
PUB 77354
PUB 77355
PUB 77368
CenturyLink ™ Engineering Standards
Guidelines for Product Change Notices
Grounding - Central Office and Remote Equipment Environment
Commercial Customer Premises Electronic Equipment
Environmental Specifications and Installation Guide
17.3 Miscellaneous Publications
API 1615 Installation of Underground Petroleum Storage Systems
API 1632
ASME B31
Cathodic Protection of Underground Petroleum Storage Tanks and
Piping Systems
Code for Pressure Piping
ASTM A-53
ASTM B-3
ASTM B-8
Standard Specification for Pipe, Steel, Black and Hot-Dipped, Zinc-
Coated, Welded and Seamless
Specifications for Soft or Annealed Copper War
ASTM B-33
ASTM B-172
ASTM B-174
Standard Specification for Concentric-Lay-Stranded Copper
Conductor, Hard, Medium-Hard, or Soft
Specifications for Tinned Soft or Annealed Copper Wire for
Electrical Purposes
Standard Specification for Rope-Lay-Stranded Copper Conductor
Having Bunch-Sheath Members, for Electrical Conductors
Standard Specification for Bunch-Stranded Copper Conductors for
Electrical Conductors
ASTM B-187
ASTM B-193
ASTM B-258
ASTM D-975
Standard Specification for Copper, Bus Bar, Rod, and Shapes, and
General Purpose Rod, Bar, and Shapes
Standard Test Method for Resistivity of Electrical Conductor
Materials
Standard Specification for Standard Nominal Diameters and Cross-
Sectional Areas of AWG Sizes of Solid Round Wires Uses as
Electrical Conductors
Standard Specification for Diesel Fuel Oils
17-3
Chapter 17
Bibliography
ASTM E-1004
ASTM E-1430
ATIS-0600003
ATIS-0600015
ATIS-0600017
ATIS-0600028
ATIS-0600311
ATIS-0600315
ATIS-0600317
ATIS-0600328
ATIS-0600330
ATIS-0600332
ATIS-0600337
ATIS-0600418
PUB 77385
Issue K, July 2015
Standard Test Method for Determining Electrical Conductivity
Using the Electromagnetic (Eddy-Current) Method
Standard Guide for Using Release Detection Devices with
Underground Storage Tanks
Battery Enclosure and Rooms/Areas
Energy Efficiency for Telecommunications Equipment:
Methodology for Measurement and Reporting DC Power Plant –
Rectifier Requirements
DC Power Wire and Cable for Telecommunications Power Systems
DC Power Wire and Cable for Telecommunications Power Systems
– for XHHW and DLO/Halogenated RHW/RHH Cable Types
DC Power Systems – Telecommunications Environment Protection
Voltage Levels for DC-Powered Equipment Used in the
Telecommunications Environment
Uniform Language for Accessing Power Plants – Human-Machine
Language
Protection of Telecommunications Links from Physical Stress and
Radiation Effects and Associated Requirements for DC Power
Systems (a Baseline Standard)
Valve-Regulated Lead-Acid Batteries Used in the
Telecommunications Environment
Electrical Protection of Network-Powered Broadband Facilities
Maximum Voltage, Current, and Power Levels in Network-
Powered Transport Systems
Hi-Bit Rate Digital Subscriber Line-Second Generation
(HDSL2/HDSL4)
Enersys AE-080123.4 Temperature Compensation Factors for OCV (Open-Circuit
Voltage), Float Voltage, and Electrolyte Specific Gravity
EPA 40CFR Part 60, Standards of Performance for New Stationary Sources; Part
63, Air Programs, National Emission Standards for Hazardous Air
Pollutants for Source Categories; Part 94, Control of Emissions from
Marine Compression-Ignition Engines; Part 112, Water Programs,
Oil Pollution Prevention and Response; and Parts 280-281,
Underground Storage Tanks Containing Petroleum
17-4
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ICBO UBC ™
ICC IBC
ICC IFC
ICC IMC
IEC 60228
IEC 60309
IEC 60417
IEC 60479
IEC 61000-3
IEC 61204-7
Chapter 17
Bibliography the Uniform Building Code
International Building Code
International Fire Code
International Mechanical Code
Conductors of Insulated Cables
Plugs, Socket-Outlets, and Couplers for Industrial Purposes
Graphical Symbols for Use on Equipment
Effects of Current on Human Beings and Livestock
Electromagnetic Compatibility (EMC) – Part 3: Limits
Low Voltage Power Supplies, D.C. Output – Part 7
IEC 62602 Conductors of Insulated Cables – Data for AWG and kcmil Sizes
IEC BS EN 13636 Cathodic Protection of Buried Metallic Tanks and Related Piping
IEEE 115
IEEE 484
Test Procedures for Synchronous Machines
Recommended Practice for the Design and Installation of Vented
Lead-Acid Batteries for Stationary Applications
IEEE 485
IEEE 519
IEEE 937
IEEE 946
Recommended Practice for Sizing Lead-Acid Batteries for
Stationary Applications
Recommended Practices and Requirements for Harmonic Control in Electrical Power Systems
Recommended Practice for Installation and Maintenance of Lead-
Acid Batteries for PhotoVoltaic (PV) Systems
Recommended Practice for the Design of DC Auxiliary Power
Systems for Generating Systems
IEEE 1013
IEEE 1106
IEEE 1115
IEEE 1184
Recommended Practice for Sizing Lead-Acid Batteries for
PhotoVoltaic (PV) Systems
Recommended Practice for Installation, Maintenance, Testing and
Replacement of Vented Nickel-Cadmium Batteries for Stationary
Applications
Recommended Practice for Sizing Nickel-Cadmium Batteries for
Stationary Applications
Recommended Practice for the Selection and Sizing of Batteries for
Uninterruptible Power Systems
17-5
IEEE C37.29
IEEE C62.11
IEEE C62.22
IEEE C62.34
IEEE C62.35
17-6
Chapter 17
Bibliography
IEEE 1187
IEEE 1189
IEEE 1361
IEEE 1375
IEEE 1491
IEEE 1562
IEEE 1578
IEEE 1635
IEEE 1657
IEEE C2
IEEE C37.2
IEEE C37.13
IEEE C37.16
PUB 77385
Issue K, July 2015
Recommended Practice for the Design and Installation of Valve-
Regulated Lead-Acid Storage Batteries for Stationary Applications
Guide for the Selection of Valve-Regulated Lead-Acid Batteries for
Stationary Applications
Guide for Selection, Charging, Test and Evaluation of Lead-Acid
Batteries Used in Stand-Alone PhotoVoltaic (PV) Systems
Guide for the Protection of Large Stationary Battery Systems
Guide for Selection and Use of Battery Monitoring Equipment in
Stationary Applications
Guide for Array and Battery Sizing in Stand-Alone PhotoVoltaic
(PV) Systems
Recommended Practice for Battery Spill Containment and
Management
Guide for the Ventilation and Thermal Management of Stationary
Battery Installations (aka ASHRAE 21)
Recommended Practice for Personnel Qualifications for the
Installation and Maintenance of Stationary Batteries
National Electrical Safety Code (NESC)
Electrical Power System Device Function Numbers and Contact
Designations
Low-Voltage AC Power Circuit Breakers Used in Enclosures
Low Voltage AC Power Circuit Breakers and AC Power Circuit
Protectors – Preferred Ratings, Related Requirements, and
Application Recommendations
Low Voltage AC Power Circuit Protectors Used in Enclosures
Metal-Oxide Surge Arrestors for Alternating Current Power
Circuits
Guide for Application of Metal-Oxide Surge Arresters for
Alternating-Current Systems
Standard for Performance of Low-Voltage Surge-Protective Devices
(Secondary Arresters)
Standard Test Specifications for Avalanche Junction Semiconductor
Surge Protective Devices
PUB 77385
Issue K, July 2015
IEEE C62.36
Chapter 17
Bibliography
IEEE C62.41
IEEE C62.41.1
IEEE C62.41.2
IEEE C62.45
IEEE C62.62
Standard Test Methods for Surge Protectors Used in Low-Voltage
Data, Communications, and Signaling Circuits
Recommended Practice for Surge Voltages in Low-Voltage AC
Power Circuits
Guide on the Surge Environment in Low-Voltage (1000V and Less)
AC Power Circuits
Recommended Practice on Characterization of Surges in Low-
Voltage (1000V and Less) AC Power Circuits
Recommended Practice on Surge Testing for Equipment Connected to Low-Voltage (1000V and Less) AC Power Circuits
Standard Test Specifications for Surge-Protective Devices for Low
Voltage AC Power Circuits
IEEE C62.64
IEEE C84.1
ISO 8528-5
NETA
NFPA
NFPA
™
®
®
ATS
1
30
Standard Specifications for Surge Protectors Used in Low-Voltage
Data, Communications and Signaling Circuits
Electrical Power Systems and Equipment — Voltage Ratings (60
Hz)
Reciprocating Internal Combustion Engine Driven Alternating
Current Generating Sets
ITU-T K.50 Safe Limits of Operating Voltages and Currents for
Telecommunications Systems
NACE ® RP0169 Control of External Corrosion on Submerged or Underground
Metallic Piping Systems
NACE ® RP0285 Corrosion Control of Underground Storage Tank Systems by
Cathodic Protection
NEMA ® ICS 10
NEMA ® LS 1
Part 1: Electromechanical AC Transfer Switch Equipment
Low Voltage Surge Suppression Devices
NEMA ® MG 1
NEMA ® WD 6
NEMA ® Z535
Motors and Generators
Wiring Devices – Dimensional Specifications
Safety Color Code – Environmental Facility Signs – Criteria for
Safety Symbols – Product Safety Sign and Labels, and Accident
Prevention Tags
Acceptance Testing Specification
(Uniform) Fire Code
Flammable and Combustible Liquid Code
17-7
PEI ™ RP100
RUS 1751F-810
RUS 1753E-001
STI ® F894
STI ® F961
STI ® R972
TIA ® 942
UL ® 4
UL ® 6
UL ® 21
UL ® 44
17-8
Chapter 17
Bibliography
NFPA ® 37
NFPA ® 58
NFPA ® 70
NFPA ® 70E
NFPA ® 76
NFPA ® 101
NFPA ® 110
NFPA ® 111
NFPA ® 704
NIOSH 98-131
OSHA 29CFR
PUB 77385
Issue K, July 2015
Standard for the Installation and Use of Stationary Combustion
Engines and Gas Turbines
Liquified Petroleum Gas Code
National Electrical Code
Standard for Electrical Safety in the Workplace
Standard for the Fire Protection of Telecommunications Facilities
Life Safety Code
Standard for Emergency and Standby Power Systems
Standard on Stored Electrical Energy Emergency and Standby
Power Systems
Standard System for the Identification of Hazards of Materials for
Emergency Response
Worker Deaths by Electrocution
Part 1910, Department of Labor, Occupational Safety and Health
Standards
Recommended Practices for Installation of Underground Liquid
Storage Systems
Electrical Protection of Digital and Lightwave Telecommunications
Equipment
General Specification for Digital, Stored Program Controlled
Central Office Equipment
ACT-100 ® Specification for External Corrosion Protection of FRP
Composite Steel USTs
ACT-100-U Specification for External Corrosion Protection of
Composite Steel USTs
Recommended Practice for the Installation of Supplemental
Anodes for STI-P3 ® USTs
Telecommunications Infrastructure Standard for Data Centers
Armored Cable
Electrical Rigid Metal Conduit – Steel
LP-Gas Hose
Thermoset-Insulated Wires and Cables
UL ® 98
UL ® 142
UL ® 144
UL ® 231
UL ® 248
UL ® 310
UL ® 347
UL ® 360
UL ® 363
UL ® 414
UL ® 429
UL ® 444
UL ® 452
UL ® 486
UL ® 489
PUB 77385
Issue K, July 2015
UL ® 50
UL ® 58
UL
UL ® 67
UL ® 83
UL ® 94
UL
UL
UL
®
®
®
®
62
497
498
UL ® 514A
UL ® 514B
UL ® 514C
514D
Chapter 17
Bibliography
Enclosures for Electrical Equipment
Safety for Steel Underground Tanks for Flammable and
Combustible Liquids
Flexible Cords and Cables
Panelboards
Thermoplastic Insulated Wires and Cables
Test for Flammability of Plastic Materials for Parts in Devices and
Applications
Enclosed and Dead-Front Switches
Steel Aboveground Tanks for Flammable and Combustible Liquids
LP-Gas Regulators
Power Outlets
Low Voltage Fuses
Electrical Quick-Connect Terminals
Medium-Voltage AC Contactors, Controllers, and Control Centers
Liquid-Tight Flexible Steel Conduit
Knife Switches
Meter Sockets
Electrically Operated Valves
Communications Cables
Antenna – Discharge Units
Wire Connectors
Molded-Case Circuit Breakers, Molded-Case Switches, and Circuit
Breaker Enclosures
Protectors for Paired-Conductor Communications Circuits
Attachment Plugs and Receptacles
Metallic Outlet Boxes
Conduit, Tubing, and Cable Fittings
Nonmetallic Outlet Boxes, Flush-Device Boxes, and Covers
Cover Plates for Flush-Mounted Wiring Devices
17-9
Chapter 17
Bibliography
UL ® 536
UL ® 644
UL ® 651
UL ® 719
UL ® 746C
UL ® 746E
UL ® 797
UL ® 810
UL ® 817
UL ® 842
UL ® 845
UL ® 854
UL ® 857
UL ® 860
UL ® 869A
UL ® 870
UL ® 891
UL ® 916
UL ® 924
UL ® 935
UL ® 943
UL ® 971
UL ® 977
UL ® 1004-1
UL ® 1004-4
UL ® 1008
UL ® 1012
17-10
PUB 77385
Issue K, July 2015
Flexible Metallic Hose
Container Assemblies for LP Gas
Schedule 40 and 80 Conduit
Nonmetallic-Sheathed Cables
Polymeric Materials – Use in Electrical Equipment Evaluations
Polymeric Materials – Industrial Laminates, Filament Wound
Tubing, Vulcanized Fibre, and Materials Used In Printed-Wiring
Boards
Electrical Metallic Tubing
Capacitors
Cord Sets and Power-Supply Cords
Valves for Flammable Fluids
Motor Control Centers
Service-Entrance Cables
Busways
Pipe Unions for Flammable and Combustible Fluids and Fire-
Protection Service
Service Equipment
Wireways, Auxiliary Gutters, and Associated Fittings
Switchboards
Energy Management Equipment
Emergency Lighting and Power Equipment
Flourescent-Lamp Ballasts
Ground-Fault Circuit-Interrupters
Non-Metallic Underground Piping for Flammable Liquids
Fused Power-Circuit Devices
Rotating Electrical Machines – General Requirements
Electric Generators
Transfer Switch Equipment
Power Units Other Than Class 2
UL ® 1437
UL ® 1441
UL ® 1446
UL ® 1449
UL ® 1479
UL ® 1558
UL ® 1561
UL ® 1562
UL ® 1564
UL ® 1581
UL ® 1598
UL ® 1642
UL ® 1653
UL ® 1659
PUB 77385
Issue K, July 2015
UL ® 1053
UL ® 1059
UL ® 1066
UL ® 1072
UL ® 1236
UL
UL
UL
UL
UL
UL
UL
®
®
®
®
®
®
®
1244
1316
1681
1682
1686
1703
1741
Chapter 17
Bibliography
Ground-Fault Sensing and Relaying Equipment
Terminal Blocks
Low Voltage AC and DC Power Circuit Breakers Used in
Enclosures
Medium-Voltage Power Cables
Battery Chargers for Charging Engine Start Batteries
Electrical and Electronic Measuring and Testing Equipment
Glass-Fiber-Reinforced Plastic Underground Storage Tanks for
Petroleum Products
Electrical Analog Instruments – Panel Board Types
Coated Electrical Sleeving
Systems of Insulating Materials
Transient Voltage Surge Suppressors
Fire Tests of Through-Penetration Firestops
Metal-Enclosed Low-Voltage Power Circuit Breaker Switchgear
Dry-Type General Purpose and Power Transformers
Transformers, Distribution, Dry-Type – Over 600 Volts
Industrial Battery Chargers
Wires, Cables, and Flexible Cords
Luminaires
Lithium Batteries
Electrical Nonmetallic Tubing
Attachment Plug Blades for Use in Cord Sets and Power-Supply
Cords
Wiring Device Configurations
Plugs, Receptacles, and Cable Connectors of the Pin and Sleeve
Type
Pin and Sleeve Configurations
Flat-Plate Photovoltaic Modules and Panels
Inverters, Converters, Controllers and Interconnection System
Equipment for Use With Distributed Energy Resources
17-11
Chapter 17
Bibliography
UL ® 1746
UL
UL
UL
UL
®
®
®
®
1773
1778
1863
1977
UL ® 1989
UL ® 1993
UL
UL
UL
UL
UL
®
®
®
®
®
1994
2024
2075
2080
2085
PUB 77385
Issue K, July 2015
External Steel Corrosion System for Steel Underground Storage
Tanks
Termination Boxes
Uninterruptible Power Systems
Communications-Circuit Accessories
Component Connectors for Use in Data, Signal, Control and Power
Applications
Standby Batteries
Self-Ballasted Lamps and Lamp Adapters
Luminous Egress Path Marking Systems
Signaling, Optical Fiber and Communications Raceways and Cable
Routing Assemblies
Gas and Vapor Detectors and Sensors
Fire Resistant Tanks for Flammable and Combustible Liquids
Protected Aboveground Tanks for Flammable and Combustible
Liquids
Tests for Fire Resistive Cables
Stationary Engine Generator Assemblies
UL ® 2196
UL ® 2200
UL ® 2201
UL ® 2239
UL ® 2245
UL ® 2344
UL ® 2367
Portable Engine Generator Assemblies
Hardware for the Support of Conduit, Tubing, and Cable
Below-Grade Vaults for Flammable Liquid Storage Tanks
Material Lifts
Solid State Overcurrent Protectors
UL ® 2556
UL ® 4248
UL ® 5085
Wire and Cable Test Methods
Fuseholders
Low Voltage Transformers
UL ® 60947-1 Low-Voltage Switchgear and Controlgear – Part 1: General rules
UL ® 60974-4-1A Low-Voltage Switchgear and Controlgear – Part 4-1: Contactors and motor-starters – Electromechanical contactors and motorstarters
17-12
PUB 77385
Issue K, July 2015
UL ® 60947-7
Chapter 17
Bibliography
Low-Voltage Switchgear and controlgear – Part 7: Ancillary equipment – Terminal blocks
UL ® 1950/60950-1 Information Technology Equipment – Safety – Part 1: General
Requirements
UL ® 60950-21
UL
UL
®
®
60950-22
61131-2
Information Technology Equipment – Safety – Part 21: Remote
Power Feeding
Information Technology Equipment – Safety – Part 22: Equipment to be Installed Outdoors
Standard for Programmable Controllers – Part 2: Equipment
Requirements and Tests
WFCA UFC ™ Uniform Fire Code
17.4 Ordering Information
All documents are subject to change and their citation in this document reflects the most current information available at the time of printing.
Obtain:
Alliance for Telecommunications Industry Solutions (ATIS) documents from:
Alliance for Telecommunications Industry Solutions
1200 G St. NW
Washington, DC 20005
Phone: (202) 628-6380
Fax: (202) 393-5453 www.atis.org
American Petroleum Institute (API) documents from:
American Petroleum Institute
1220 L St. NW
Washington, DC 20005-4070
Phone: (202) 682-8000 www.api.org
American Society of Mechanical Engineers (ASME) documents from:
American Society of Mechanical Engineers
3 Park Ave.
New York, NY 10016
Phone: (800) 843-2763 www.asme.org
17-13
Chapter 17
Bibliography
American Society for the Testing of Materials (ASTM) documents from:
PUB 77385
Issue K, July 2015
American Society for the Testing of Materials
100 Bar Harbor Dr.
P.O. Box C700
West Conshohocken, PA 19428
Phone: (610) 832-9585
Fax: (610) 832-9555 www.astm.com
CenturyLink ™ Technical Publications from: www.centurylink.com/techpub
Enersys documents from: www.enersysreservepower.com
Federal Regulations from: www.gpo.gov/fdsys
International Building and Fire Code documents from:
International Code Council
5203 Leesburg Pike, Ste. 600
Falls Church, VA 22041
Phone: (703) 931-4533 www.iccsafe.org
IEC documents from:
International Electrotechnical Commission
3, rue de Varembé
P.O. Box 131
CH – 1211 Geneva 20
Switzerland
Phone: +41 22 919 02 11
Fax: +41 22 919 03 00 www.iec.ch
17-14
PUB 77385
Issue K, July 2015
IEEE documents from:
IEEE Customer Service Center
445 Hoes Lane
Piscataway NJ, 08855-1331
Phone: (800) 678-4333
Fax: (732) 981-9667 www.ieee.org
ISO documents from:
International Organization for Standardization
1, ch. De la Voie-Creuse
CP 56 – CH-1211 Geneva 20
Switzerland
Phone: +41 22 749 01 11
Fax: +41 22 733 34 30 www.iso.org
ITU documents from:
International Telecommunications Union
Place des Nations
1211 Geneva 20
Switzerland
Phone: +41 22 730 6141
Fax: +41 22 730 5194 www.itu.int
NACE ® documents from:
NACE Headquarters
1440 S. Creek Dr.
Houston TX, 77084-4906
Phone: (800) 797-6223
Fax: (281) 228-6300 www.nace.org
NEMA ® documents from:
National Electrical Manufacturers Association www.nema.org
Chapter 17
Bibliography
17-15
Chapter 17
Bibliography
NETA ™ documents from:
InterNational Electrical Testing Association
3050 Old Centre Ave., Ste. 102
Portage MI, 49024
Phone: (269) 488-6382
Fax: (269) 488-6383 www.netaworld.org
NFPA ® documents from:
NFPA Customer Sales
1 Batterymarch Park
Quincy, MA 02269-9101
Phone: (800) 344-3555
Fax: (617) 770-0700 www.nfpa.org
PUB 77385
Issue K, July 2015
NIOSH documents from: the National Institute for Occupational Safety and Health
1600 Clifton Rd.
Rm. 4505, MS E-20
Atlanta, GA 30333
Phone: (800) 232-4636
Fax: (513) 533-8347 www.cdc.gov/niosh
Petroleum Equipment Institute (PEI ™ ) documents from:
Petroleum Equipment Institute
P.O. Box 2380
Tulsa, OK 74101-2380
Phone: (918) 494-9696
Fax: (918) 491-9895 www.pei.org
RUS documents from:
United States Department of Agriculture Rural Development
1400 Independence Ave. SW
Washington, DC 20250-0107
Phone: (202) 720-8674 www.rurdev.usda.gov/RDU_Bulletins_Telecommunications.html
17-16
PUB 77385
Issue K, July 2015
Telcordia ® documents from:
Telcordia - Customer Services
8 Corporate Place
Piscataway, NJ 08854-4196
Telex: (201) 275-2090
Fax: (908) 336-2559
Phone: (800) 521-2673 www.telcordia.com
TIA ® documents from:
Telecommunications Industry Association
2500 Wilson Blvd., Ste. 300
Arlington, VA 22201
Fax: (703) 907-7727
Phone: (703) 907-7700 www.tiaonline.org
UL ® documents from:
Underwriters Laboratories
Phone: (888) 853-3503 www.ul.com
Chapter 17
Bibliography
17-17
